Development of a socketed foundation for the Midwest Weak Post (MWP) v1.

DOT National Transportation Integrated Search

2014-07-01

A socketed foundation was designed and evaluated for use with the Midwest Weak Post (MWP), Version 1. : Dynamic component testing was conducted on five different design configurations with varying embedment : depths, steel reinforcement, and soil con...

Head-Up; An interdisciplinary, participatory and co-design process informing the development of a novel head and neck support for people living with progressive neck muscle weakness.

PubMed

Reed, Heath; Langley, Joe; Stanton, Andy; Heron, Nicola; Clarke, Zoe; Judge, Simon; McCarthy, Avril; Squire, Gill; Quinn, Ann; Wells, Oliver; Tindale, Wendy; Baxter, Susan; Shaw, Pamela J; McDermott, Christopher J

2014-01-01

This paper presents the Head-Up project, that aims to provide innovative head support to help improve posture, relieve pain and aid communication for people living with progressive neck muscle weakness. The initial focus is motor neurone disease. The case study illustrates collaborative, interdisciplinary research and new product development underpinned by participatory design. The study was initiated by a 2-day stakeholder workshop followed by early proof-of-concept modelling and patient need evidence building. The work subsequently led to a successful NIHR i4i application funding a 24-month iterative design process, patenting, CE marking and clinical evaluation. The evaluation has informed amendments to the proposed design refered to here as the Sheffield Support Snood (SSS). The outcome positively demonstrates use and performance improvements over current neck orthoses and the process of multidisciplinary and user engagement has created a sense of ownership by MND participants, who have since acted as advocates for the product.

Strengthening the Regression Discontinuity Design Using Additional Design Elements: A Within-Study Comparison

ERIC Educational Resources Information Center

Wing, Coady; Cook, Thomas D.

2013-01-01

The sharp regression discontinuity design (RDD) has three key weaknesses compared to the randomized clinical trial (RCT). It has lower statistical power, it is more dependent on statistical modeling assumptions, and its treatment effect estimates are limited to the narrow subpopulation of cases immediately around the cutoff, which is rarely of…

Persistence of noncompact normally hyperbolic invariant manifolds in bounded geometry

NASA Astrophysics Data System (ADS)

Edwards, Monroe

Traveling wave tubes must operate in a metal and ceramic vacuum for efficient electron amplification. Weak metallize bonds lead to vacuum leaks and a higher cost of poor quality. The management of TWT Manufacturing (pseudonym) has used a team of metallize workers to attack the problem through brainstorming and subsequent design of experiments (DOE). The purpose of the DOE, which is the focus of this project, is to determine if certain parameters can be changed to increase the strength enough to eliminate failures to weak metallize bonds. The experimental results show the strength can be increased enough and have been recorded in the process instructions. The implementation of the DOE results has saved over nine percent in the budgeted cost of weak metallize bond scrap. This study concludes that raising the metallize tensile strength practically eliminates weak metallize bonds and the cost of poor quality due to this weakness.

[Coalition tactics of the weaks in the power struggle].

PubMed

Yamaguchi, H

1991-02-01

This study was intended to investigate the coalition tactics of the weaks under the situation where four players in the power relationship such as "A greater than B = C = D, A less than (B + C + D)" struggled for new resources of power. Subjects were 128 male undergraduates divided into 32 groups of four members each. The experimental design was 2 (determinants of power strength; resource size or rank order) x 2 (range of power distance between the strong and the weaks; large or small). As the result, it was revealed that the weaks preferred revolutional coalition "BCD" under the condition where the resource size determined the power strength, while preferred getting-ahead coalition "AB, AC, AD" under the condition where the rank order determined, and that expansion of power distance reinforced such tendency of the weaks. It was also shown, however, that the weaks did not always form the coalitions as they had hoped before bargaining. In conclusion, the necessity to examine the characteristics of the weaks' mentalities and behaviors in coalition bargaining was suggested.

Precise design-based defect characterization and root cause analysis

NASA Astrophysics Data System (ADS)

Xie, Qian; Venkatachalam, Panneerselvam; Lee, Julie; Chen, Zhijin; Zafar, Khurram

2017-03-01

As semiconductor manufacturing continues its march towards more advanced technology nodes, it becomes increasingly important to identify and characterize design weak points, which is typically done using a combination of inline inspection data and the physical layout (or design). However, the employed methodologies have been somewhat imprecise, relying greatly on statistical techniques to signal excursions. For example, defect location error that is inherent to inspection tools prevents them from reporting the true locations of defects. Therefore, common operations such as background-based binning that are designed to identify frequently failing patterns cannot reliably identify specific weak patterns. They can only identify an approximate set of possible weak patterns, but within these sets there are many perfectly good patterns. Additionally, characterizing the failure rate of a known weak pattern based on inline inspection data also has a lot of fuzziness due to coordinate uncertainty. SEM (Scanning Electron Microscope) Review attempts to come to the rescue by capturing high resolution images of the regions surrounding the reported defect locations, but SEM images are reviewed by human operators and the weak patterns revealed in those images must be manually identified and classified. Compounding the problem is the fact that a single Review SEM image may contain multiple defective patterns and several of those patterns might not appear defective to the human eye. In this paper we describe a significantly improved methodology that brings advanced computer image processing and design-overlay techniques to better address the challenges posed by today's leading technology nodes. Specifically, new software techniques allow the computer to analyze Review SEM images in detail, to overlay those images with reference design to detect every defect that might be present in all regions of interest within the overlaid reference design (including several classes of defects that human operators will typically miss), to obtain the exact defect location on design, to compare all defective patterns thus detected against a library of known patterns, and to classify all defective patterns as either new or known. By applying the computer to these tasks, we automate the entire process from defective pattern identification to pattern classification with high precision, and we perform this operation en masse during R & D, ramp, and volume production. By adopting the methodology, whenever a specific weak pattern is identified, we are able to run a series of characterization operations to ultimately arrive at the root cause. These characterization operations can include (a) searching all pre-existing Review SEM images for the presence of the specific weak pattern to determine whether there is any spatial (within die or within wafer) or temporal (within any particular date range, before or after a mask revision, etc.) correlation and (b) understanding the failure rate of the specific weak pattern to prioritize the urgency of the problem, (c) comparing the weak pattern against an OPC (Optical Procimity Correction) Verification report or a PWQ (Process Window Qualification)/FEM (Focus Exposure Matrix) result to assess the likelihood of it being a litho-sensitive pattern, etc. After resolving the specific weak pattern, we will categorize it as known pattern, and the engineer will move forward with discovering new weak patterns.

Bivariate spline solution of time dependent nonlinear PDE for a population density over irregular domains.

PubMed

Gutierrez, Juan B; Lai, Ming-Jun; Slavov, George

2015-12-01

We study a time dependent partial differential equation (PDE) which arises from classic models in ecology involving logistic growth with Allee effect by introducing a discrete weak solution. Existence, uniqueness and stability of the discrete weak solutions are discussed. We use bivariate splines to approximate the discrete weak solution of the nonlinear PDE. A computational algorithm is designed to solve this PDE. A convergence analysis of the algorithm is presented. We present some simulations of population development over some irregular domains. Finally, we discuss applications in epidemiology and other ecological problems. Copyright © 2015 Elsevier Inc. All rights reserved.

Improvement of the geotechnical axial design methodology for Colorado's drilled shafts socketed in weak rocks

DOT National Transportation Integrated Search

2003-07-01

Drilled shaft foundations embedded in weak rock formations (e.g., Denver blue claystone and sandstone) support a significant portion of bridges in Colorado. Since the 1960s, empirical methods and rules of thumb have been used to design drilled shafts...

Performance-Based Seismic Design of Steel Frames Utilizing Colliding Bodies Algorithm

PubMed Central

Veladi, H.

2014-01-01

A pushover analysis method based on semirigid connection concept is developed and the colliding bodies optimization algorithm is employed to find optimum seismic design of frame structures. Two numerical examples from the literature are studied. The results of the new algorithm are compared to the conventional design methods to show the power or weakness of the algorithm. PMID:25202717

Performance-based seismic design of steel frames utilizing colliding bodies algorithm.

PubMed

Veladi, H

2014-01-01

A pushover analysis method based on semirigid connection concept is developed and the colliding bodies optimization algorithm is employed to find optimum seismic design of frame structures. Two numerical examples from the literature are studied. The results of the new algorithm are compared to the conventional design methods to show the power or weakness of the algorithm.

Collaborative, Sequential and Isolated Decisions in Design

NASA Technical Reports Server (NTRS)

Lewis, Kemper; Mistree, Farrokh

1997-01-01

The Massachusetts Institute of Technology (MIT) Commission on Industrial Productivity, in their report Made in America, found that six recurring weaknesses were hampering American manufacturing industries. The two weaknesses most relevant to product development were 1) technological weakness in development and production, and 2) failures in cooperation. The remedies to these weaknesses are considered the essential twin pillars of CE: 1) improved development process, and 2) closer cooperation. In the MIT report, it is recognized that total cooperation among teams in a CE environment is rare in American industry, while the majority of the design research in mathematically modeling CE has assumed total cooperation. In this paper, we present mathematical constructs, based on game theoretic principles, to model degrees of collaboration characterized by approximate cooperation, sequential decision making and isolation. The design of a pressure vessel and a passenger aircraft are included as illustrative examples.

Transfusion strategy for weak D type 4.0 based on RHD alleles and RH haplotypes in Tunisia

PubMed Central

Ouchari, Mouna; Srivastava, Kshitij; Romdhane, Houda; Yacoub, Saloua Jemni; Flegel, Willy Albert

2017-01-01

Background With more than 460 RHD alleles, this gene is the most complex and polymorphic among all blood group systems. The Tunisian population has the largest known prevalence of weak D type 4.0 alleles, occurring in 1 of 105 RH haplotypes. We aimed to establish a rationale for the transfusion strategy of weak D type 4.0 in Tunisia. Study design and methods Donors were randomly screened for the serological weak D phenotype. The RHD coding sequence and parts of the introns were sequenced. To establish the RH haplotype, the RHCE gene was tested for characteristic single nucleotide positions. Results We determined all RHD alleles and the RH haplotypes coding for the serologic weak D phenotype among 13,431 Tunisian donations. A serologic weak D phenotype was found in 67 individuals (0.50%). Among them, 60 carried a weak D type 4 allele: 53 weak D type 4.0, 6 weak D type 4.2.2 (DAR), and 1 weak D type 4.1. Another 4 donors had 1 variant allele each: DVII, weak D type 1, weak D type 3, and weak D type 100, while 3 donors showed a normal RHD sequence. The weak D type 4.0 was most often linked to RHCE*ceVS.04.01, weak D type 4.2.2 to RHCE*ceAR, and weak D type 4.1 to RHCE*ceVS.02, while the other RHD alleles were linked to one of the common RHCE alleles. Conclusions Among the weak D phenotypes in Tunisia, no novel RHD allele was found and almost 90% were caused by alleles of the weak D type 4 cluster, of which 88% represented the weak D type 4.0 allele. Based on established RH haplotypes for variant RHD and RHCE alleles and the lack of adverse clinical reports, we recommend D positive transfusions for patients with weak D type 4.0 in Tunisia. PMID:29193104

Effect of strong-column weak-beam design provision on the seismic fragility of RC frame buildings

NASA Astrophysics Data System (ADS)

Surana, Mitesh; Singh, Yogendra; Lang, Dominik H.

2018-04-01

Incremental dynamic analyses are conducted for a suite of low- and mid-rise reinforced-concrete special moment-resisting frame buildings. Buildings non-conforming and conforming to the strong-column weak-beam (SCWB) design criterion are considered. These buildings are designed for the two most severe seismic zones in India (i.e., zone IV and zone V) following the provisions of Indian Standards. It is observed that buildings non-conforming to the SCWB design criterion lead to an undesirable column failure collapse mechanism. Although yielding of columns cannot be avoided, even for buildings conforming to a SCWB ratio of 1.4, the observed collapse mechanism changes to a beam failure mechanism. This change in collapse mechanism leads to a significant increase in the building's global ductility capacity, and thereby in collapse capacity. The fragility analysis study of the considered buildings suggests that considering the SCWB design criterion leads to a significant reduction in collapse probability, particularly in the case of mid-rise buildings.

A Randomized Crossover Study of Web-Based Media Literacy to Prevent Smoking

ERIC Educational Resources Information Center

Shensa, Ariel; Phelps-Tschang, Jane; Miller, Elizabeth; Primack, Brian A.

2016-01-01

Feasibly implemented Web-based smoking media literacy (SML) programs have been associated with improving SML skills among adolescents. However, prior evaluations have generally had weak experimental designs. We aimed to examine program efficacy using a more rigorous crossover design. Seventy-two ninth grade students completed a Web-based SML…

Different Versions of the Same Lesson Plan: Implications on the Lesson Design

ERIC Educational Resources Information Center

Greenlees, Jane; Patahuddin, Sitti Maesuri; Lowrie, Tom

2014-01-01

The World Bank 2007 TIMSS Video Study provided a distinctive insight into the practices of the Indonesian classroom and identified key strengths and weaknesses of current teaching. This investigation considered this evidence in the development of a structured lesson design that specifically addressed the instructional practices of the teaching and…

The Littoral Combat Ship: Is the US Navy Assuming Too Much Risk?

DTIC Science & Technology

2006-06-16

whereas the General Dynamics design will focus on an all- aluminum trimaran hull. Additional study of the pros and cons based on these two designs and......also important to understand that not all risk is bad. The SWOT analysis, which looks at the strengths, weaknesses, opportunities, and threats

Newcastle Disease Virus (PDQ®)—Health Professional Version

Cancer.gov

Newcastle disease virus (NDV)- based therapy has been reported to be of benefit in clinical studies, but results are considered inconclusive. Study designs were weak and the study reports were generally incomplete. Get detailed information about NDV use in cancer in this summary for clinicians.

Evaluation of hospital palliative care teams: strengths and weaknesses of the before-after study design and strategies to improve it.

PubMed

Simon, S; Higginson, I J

2009-01-01

Hospital palliative care teams (HPCTs) are well established as multi-professional services to provide palliative care in an acute hospital setting and are increasing in number. However, there is still limited evaluation of them, in terms of efficacy and effectiveness. The gold standard method of evaluation is a randomised control trial, but because of methodological (e.g., randomisation), ethical and practical difficulties such trials are often not possible. HPCT is a complex intervention, and the specific situation in palliative care makes it challenging to evaluate (e.g., distress and cognitive impairment of patients). The quasi-experimental before-after study design has the advantage of enabling an experimental character without randomisation. But this has other weaknesses and is prone to bias, for example, temporal trends and selection bias. As for every study design, avoidance and minimisation of bias is important to improve validity. Therefore, strategies of selecting an appropriate control group or time series and applying valid outcomes and measurement tools help reducing bias and strengthen the methods. Special attention is needed to plan and define the design and applied method.

Design of weak link channel-cut crystals for fast QEXAFS monochromators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Polheim, O. von, E-mail: vonpolheim@uni-wuppertal.de; Müller, O.; Lützenkirchen-Hecht, D.

2016-07-27

A weak link channel-cut crystal, optimized for dedicated Quick EXAFS monochromators and measurements, was designed using finite element analysis. This channel-cut crystal offers precise detuning capabilities to enable suppression of higher harmonics in the virtually monochromatic beam. It was optimized to keep the detuning stable, withstanding the mechanical load, which occurs during oscillations with up to 50 Hz. First tests at DELTA (Dortmund, Germany), proved the design.

Mass Mapping Abell 2261 with Kinematic Weak Lensing: A Pilot Study for NASAs WFIRST mission

NASA Astrophysics Data System (ADS)

Eifler, Tim

2015-02-01

We propose to investigate a new method to extract cosmological information from weak gravitational lensing in the context of the mission design and requirements of NASAs Wide-Field Infrared Survey Telescope (WFIRST). In a recent paper (Huff, Krause, Eifler, George, Schlegel 2013) we describe a new method for reducing the shape noise in weak lensing measurements by an order of magnitude. Our method relies on spectroscopic measurements of disk galaxy rotation and makes use of the well-established Tully-Fisher (TF) relation in order to control for the intrinsic orientations of galaxy disks. Whereas shape noise is one of the major limitations for current weak lensing experiments it ceases to be an important source of statistical error in our new proposed technique. Specifically, we propose a pilot study that maps the projected mass distribution in the massive cluster Abell 2261 (z=0.225) to infer whether this promising technique faces systematics that prohibit its application to WFIRST. In addition to the cosmological weak lensing prospects, these measurements will also allow us to test kinematic lensing in the context of cluster mass reconstruction with a drastically improved signal-to-noise (S/N) per galaxy.

Relationship Between Advanced Maternal Age, Hiesho (Sensitivity to Cold) and Abnormal Delivery in Japan

PubMed Central

Nakamura, Sachiyo; Horiuchi, Shigeko

2013-01-01

Background: In Japan, the proportion of women aged 35 and older giving birth has greatly increased in recent years, and maternal age is continuing to increase. Advanced maternal age is a risk factor for abnormal delivery, as is hiesho (sensitivity to cold). Research Question: This study aimed to assess whether advanced maternal age and hiesho precipitate premature delivery, premature rupture of membranes, weak labor pains, prolonged labor and atonic bleeding. Method: The study design was a descriptive comparative study with a retrospective cohort group design. Subjects in this study were 2,810 Japanese women in hospital after childbirth. The research methods employed were a paper questionnaire and extraction of data from medical records. Results: Comparing the rate of occurrence of abnormal delivery among women aged 35 to 39 according to whether or not they had hiesho, results were premature delivery OR: 3.51 (95% CI: 1.66-7.43), premature rupture of membranes OR: 1.25 (95% CI: 0.90-1.74), weak labor pains OR: 2.94 (95% CI: 1.65-5.24), prolonged labor OR: 2.56 (95% CI: 1.23-5.26), and atonic bleeding, OR: 1.65 (95% CI: 0.14-2.40) when hiesho was present. Among women aged 40 and over, results were premature delivery OR: 5.09 (95% CI: 1.16-22.20), premature rupture of membranes OR: 1.60 (95% CI: 0.73-3.46), weak labor pains OR: 7.02 (95% CI: 1.56-31.55), prolonged labor OR:7.19 (95% CI: 1.49-34.60) and atonic bleeding OR: 2.00 (95% CI: 0.64-6.23). Conclusions: Regardless of maternal age, the presence of hiesho is a risk factor that can precipitate premature delivery, premature rupture of membranes, weak labor pains, prolonged labor and atonic bleeding. Furthermore, hiesho coupled with advanced maternal age increases the incidence of premature delivery, weak labor pains and prolonged labor. PMID:24062862

Attenuation of harmonic noise in vibroseis data using Simulated Annealing

NASA Astrophysics Data System (ADS)

Sharma, S. P.; Tildy, Peter; Iranpour, Kambiz; Scholtz, Peter

2009-04-01

Processing of high productivity vibroseis seismic data (such as slip-sweep acquisition records) suffers from the well known disadvantage of harmonic distortion. Harmonic distortions are observed after cross-correlation of the recorded seismic signal with the pilot sweep and affect the signals in negative time (before the actual strong reflection event). Weak reflection events of the earlier sweeps falling in the negative time window of the cross-correlation sequence are being masked by harmonic distortions. Though the amplitude of the harmonic distortion is small (up to 10-20 %) compared to the fundamental amplitude of the reflection events, but it is significant enough to mask weak reflected signals. Elimination of harmonic noise due to source signal distortion from the cross-correlated seismic trace is a challenging task since the application of vibratory sources started and it still needs improvement. An approach has been worked out that minimizes the level of harmonic distortion by designing the signal similar to the harmonic distortion. An arbitrary length filter is optimized using the Simulated Annealing global optimization approach to design a harmonic signal. The approach deals with the convolution of a ratio trace (ratio of the harmonics with respect to the fundamental sweep) with the correlated "positive time" recorded signal and an arbitrary filter. Synthetic data study has revealed that this procedure of designing a signal similar to the desired harmonics using convolution of a suitable filter with theoretical ratio of harmonics with fundamental sweep helps in reducing the problem of harmonic distortion. Once we generate a similar signal for a vibroseis source using an optimized filter, then, this filter could be used to generate harmonics, which can be subtracted from the main cross-correlated trace to get the better, undistorted image of the subsurface. Designing the predicted harmonics to reduce the energy in the trace by considering weak reflection and observed harmonics together yields the desired result (resolution of weak reflected signal from the harmonic distortion). As optimization steps proceeds forward it is possible to observe from the difference plots of desired and predicted harmonics how weak reflections evolved from the harmonic distortion gradually during later iterations of global optimization. The procedure is applied in resolving weak reflections from a number of traces considered together. For a more precise design of harmonics SA procedure needs longer computation time which is impractical to deal with voluminous seismic data. However, the objective of resolving weak reflection signal in the strong harmonic noise can be achieved with fast computation using faster cooling schedule and less number of iterations and number of moves in simulated annealing procedure. This process could help in reducing the harmonics distortion and achieving the objective of resolving the lost weak reflection events in the cross-correlated seismic traces. Acknowledgements: The research was supported under the European Marie Curie Host Fellowships for Transfer of Knowledge (TOK) Development Host Scheme (contract no. MTKD-CT-2006-042537).

Evaluating psycho-educational interventions for informal carers of patients receiving cancer care or palliative care: strengths and limitations of different study designs.

PubMed

Schildmann, Eva K; Higginson, Irene J

2011-06-01

Despite evidence of negative psychological sequelae and unmet needs, there are few evaluated interventions for informal caregivers in cancer and palliative care. The aim of this article is to debate the strengths and limitations of randomized controlled trials (RCTs) and other designs that can be used to evaluate the effectiveness of these interventions. Psycho-educational interventions are used as example for this debate article, as a number of studies of various designs evaluating this type of intervention have been published. Systematic searching in Medline and the bibliography of a relevant systematic review identified five RCTs, one pre-test/post-test study with a control group and six one-group pre-test/post-test studies of psycho-educational interventions for caregivers. The methodological strengths and weaknesses were assessed. RCTs are seen as the gold standard, but can have important limitations in the context of carer intervention research, including biased recruitment and low generalizability, problems with blinding and attrition. Pre-test/post-test studies with a control group may be more feasible and more generalizable. Their crucial limitation is selection bias. Before-after studies are compromised by additional specific biases and therefore are the weakest of all discussed designs. After analysing the strengths and weaknesses of the mentioned study designs, this paper presents strategies to address the limitations of RCTs evaluating psycho-educational interventions for carers in cancer or palliative care. © The Author(s) 2011

Phase Diagram of the Bose Hubbard Model with Weak Links

NASA Astrophysics Data System (ADS)

Hettiarachchilage, Kalani; Rousseau, Valy; Tam, Ka-Ming; Moreno, Juana; Jarrell, Mark; Sheehy, Daniel

2012-02-01

We study the ground state phase diagram of strongly interacting ultracold Bose gas in a one-dimensional optical lattice with a tunable weak link, by means of Quantum Monte Carlo simulation. This model contains an on-site repulsive interaction (U) and two different near-neighbor hopping terms, J and t, for the weak link and the remainder of the chain, respectively. We show that by reducing the strength of J, a novel intermediate phase develops which is compressible and non-superfluid. This novel phase is identified as a Normal Bose Liquid (NBL) which does not appear in the phase diagram of the homogeneous bosonic Hubbard model. Further, we find a linear variation of the phase boundary of Normal Bose Liquid (NBL) to SuperFluid (SF) as a function of the strength of the weak link. These results may provide a new path to design advanced atomtronic devices in the future.

Designing perturbative metamaterials from discrete models.

PubMed

Matlack, Kathryn H; Serra-Garcia, Marc; Palermo, Antonio; Huber, Sebastian D; Daraio, Chiara

2018-04-01

Identifying material geometries that lead to metamaterials with desired functionalities presents a challenge for the field. Discrete, or reduced-order, models provide a concise description of complex phenomena, such as negative refraction, or topological surface states; therefore, the combination of geometric building blocks to replicate discrete models presenting the desired features represents a promising approach. However, there is no reliable way to solve such an inverse problem. Here, we introduce 'perturbative metamaterials', a class of metamaterials consisting of weakly interacting unit cells. The weak interaction allows us to associate each element of the discrete model with individual geometric features of the metamaterial, thereby enabling a systematic design process. We demonstrate our approach by designing two-dimensional elastic metamaterials that realize Veselago lenses, zero-dispersion bands and topological surface phonons. While our selected examples are within the mechanical domain, the same design principle can be applied to acoustic, thermal and photonic metamaterials composed of weakly interacting unit cells.

Subsurface Characterization using Geophysical Seismic Refraction Survey for Slope Stabilization Design with Soil Nailing

NASA Astrophysics Data System (ADS)

Ashraf Mohamad Ismail, Mohd; Ng, Soon Min; Hazreek Zainal Abidin, Mohd; Madun, Aziman

2018-04-01

The application of geophysical seismic refraction for slope stabilization design using soil nailing method was demonstrated in this study. The potential weak layer of the study area is first identify prior to determining the appropriate length and location of the soil nail. A total of 7 seismic refraction survey lines were conducted at the study area with standard procedures. The refraction data were then analyzed by using the Pickwin and Plotrefa computer software package to obtain the seismic velocity profiles distribution. These results were correlated with the complementary borehole data to interpret the subsurface profile of the study area. It has been identified that layer 1 to 3 is the potential weak zone susceptible to slope failure. Hence, soil nails should be installed to transfer the tensile load from the less stable layer 3 to the more stable layer 4. The soil-nail interaction will provide a reinforcing action to the soil mass thereby increasing the stability of the slope.

Quality and methodological challenges in Internet-based mental health trials.

PubMed

Ye, Xibiao; Bapuji, Sunita Bayyavarapu; Winters, Shannon; Metge, Colleen; Raynard, Mellissa

2014-08-01

To review the quality of Internet-based mental health intervention studies and their methodological challenges. We searched multiple literature databases to identify relevant studies according to the Population, Interventions, Comparators, Outcomes, and Study Design framework. Two reviewers independently assessed selection bias, allocation bias, confounding bias, blinding, data collection methods, and withdrawals/dropouts, using the Quality Assessment Tool for Quantitative Studies. We rated each component as strong, moderate, or weak and assigned a global rating (strong, moderate, or weak) to each study. We discussed methodological issues related to the study quality. Of 122 studies included, 31 (25%), 44 (36%), and 47 (39%) were rated strong, moderate, and weak, respectively. Only five studies were rated strong for all of the six quality components (three of them were published by the same group). Lack of blinding, selection bias, and low adherence were the top three challenges in Internet-based mental health intervention studies. The overall quality of Internet-based mental health intervention needs to improve. In particular, studies need to improve sample selection, intervention allocation, and blinding.

Medication safety research by observational study design.

PubMed

Lao, Kim S J; Chui, Celine S L; Man, Kenneth K C; Lau, Wallis C Y; Chan, Esther W; Wong, Ian C K

2016-06-01

Observational studies have been recognised to be essential for investigating the safety profile of medications. Numerous observational studies have been conducted on the platform of large population databases, which provide adequate sample size and follow-up length to detect infrequent and/or delayed clinical outcomes. Cohort and case-control are well-accepted traditional methodologies for hypothesis testing, while within-individual study designs are developing and evolving, addressing previous known methodological limitations to reduce confounding and bias. Respective examples of observational studies of different study designs using medical databases are shown. Methodology characteristics, study assumptions, strengths and weaknesses of each method are discussed in this review.

Indoor radon and childhood leukaemia.

PubMed

Raaschou-Nielsen, Ole

2008-01-01

This paper summarises the epidemiological literature on domestic exposure to radon and risk for childhood leukaemia. The results of 12 ecological studies show a consistent pattern of higher incidence and mortality rates for childhood leukaemia in areas with higher average indoor radon concentrations. Although the results of such studies are useful to generate hypotheses, they must be interpreted with caution, as the data were aggregated and analysed for geographical areas and not for individuals. The seven available case-control studies of childhood leukaemia with measurement of radon concentrations in the residences of cases and controls gave mixed results, however, with some indication of a weak (relative risk < 2) association with acute lymphoblastic leukaemia. The epidemiological evidence to date suggests that an association between indoor exposure to radon and childhood leukaemia might exist, but is weak. More case-control studies are needed, with sufficient statistical power to detect weak associations and based on designs and methods that minimise misclassification of exposure and provide a high participation rate and low potential selection bias.

Elephants in Pyjamas: Testing the Weak Central Coherence Account of Autism Spectrum Disorders Using a Syntactic Disambiguation Task

ERIC Educational Resources Information Center

Riches, N. G.; Loucas, T.; Baird, G.; Charman, T.; Simonoff, E.

2016-01-01

According to the weak central coherence (CC) account individuals with autism spectrum disorders (ASD) exhibit enhanced local processing and weak part-whole integration. CC was investigated in the verbal domain. Adolescents, recruited using a 2 (ASD status) by 2 (language impairment status) design, completed an aural forced choice comprehension…

Investigating Primary Source Literacy

ERIC Educational Resources Information Center

Archer, Joanne; Hanlon, Ann M.; Levine, Jennie A.

2009-01-01

Primary source research requires students to acquire specialized research skills. This paper presents results from a user study testing the effectiveness of a Web guide designed to convey the concepts behind "primary source literacy". The study also evaluated students' strengths and weaknesses when conducting primary source research. (Contains 3…

Optimum study designs.

PubMed

Gu, C; Rao, D C

2001-01-01

Because simplistic designs will lead to prohibitively large sample sizes, the optimization of genetic study designs is critical for successfully mapping genes for complex diseases. Creative designs are necessary for detecting and amplifying the usually weak signals for complex traits. Two important outcomes of a study design--power and resolution--are implicitly tied together by the principle of uncertainty. Overemphasis on either one may lead to suboptimal designs. To achieve optimality for a particular study, therefore, practical measures such as cost-effectiveness must be used to strike a balance between power and resolution. In this light, the myriad of factors involved in study design can be checked for their effects on the ultimate outcomes, and the popular existing designs can be sorted into building blocks that may be useful for particular situations. It is hoped that imaginative construction of novel designs using such building blocks will lead to enhanced efficiency in finding genes for complex human traits.

Stochastic Resonance in an Underdamped System with Pinning Potential for Weak Signal Detection

PubMed Central

Zhang, Haibin; He, Qingbo; Kong, Fanrang

2015-01-01

Stochastic resonance (SR) has been proved to be an effective approach for weak sensor signal detection. This study presents a new weak signal detection method based on a SR in an underdamped system, which consists of a pinning potential model. The model was firstly discovered from magnetic domain wall (DW) in ferromagnetic strips. We analyze the principle of the proposed underdamped pinning SR (UPSR) system, the detailed numerical simulation and system performance. We also propose the strategy of selecting the proper damping factor and other system parameters to match a weak signal, input noise and to generate the highest output signal-to-noise ratio (SNR). Finally, we have verified its effectiveness with both simulated and experimental input signals. Results indicate that the UPSR performs better in weak signal detection than the conventional SR (CSR) with merits of higher output SNR, better anti-noise and frequency response capability. Besides, the system can be designed accurately and efficiently owing to the sensibility of parameters and potential diversity. The features also weaken the limitation of small parameters on SR system. PMID:26343662

Stochastic Resonance in an Underdamped System with Pinning Potential for Weak Signal Detection.

PubMed

Zhang, Haibin; He, Qingbo; Kong, Fanrang

2015-08-28

Stochastic resonance (SR) has been proved to be an effective approach for weak sensor signal detection. This study presents a new weak signal detection method based on a SR in an underdamped system, which consists of a pinning potential model. The model was firstly discovered from magnetic domain wall (DW) in ferromagnetic strips. We analyze the principle of the proposed underdamped pinning SR (UPSR) system, the detailed numerical simulation and system performance. We also propose the strategy of selecting the proper damping factor and other system parameters to match a weak signal, input noise and to generate the highest output signal-to-noise ratio (SNR). Finally, we have verified its effectiveness with both simulated and experimental input signals. Results indicate that the UPSR performs better in weak signal detection than the conventional SR (CSR) with merits of higher output SNR, better anti-noise and frequency response capability. Besides, the system can be designed accurately and efficiently owing to the sensibility of parameters and potential diversity. The features also weaken the limitation of small parameters on SR system.

Study design and data analysis considerations for the discovery of prognostic molecular biomarkers: a case study of progression free survival in advanced serous ovarian cancer.

PubMed

Qin, Li-Xuan; Levine, Douglas A

2016-06-10

Accurate discovery of molecular biomarkers that are prognostic of a clinical outcome is an important yet challenging task, partly due to the combination of the typically weak genomic signal for a clinical outcome and the frequently strong noise due to microarray handling effects. Effective strategies to resolve this challenge are in dire need. We set out to assess the use of careful study design and data normalization for the discovery of prognostic molecular biomarkers. Taking progression free survival in advanced serous ovarian cancer as an example, we conducted empirical analysis on two sets of microRNA arrays for the same set of tumor samples: arrays in one set were collected using careful study design (that is, uniform handling and randomized array-to-sample assignment) and arrays in the other set were not. We found that (1) handling effects can confound the clinical outcome under study as a result of chance even with randomization, (2) the level of confounding handling effects can be reduced by data normalization, and (3) good study design cannot be replaced by post-hoc normalization. In addition, we provided a practical approach to define positive and negative control markers for detecting handling effects and assessing the performance of a normalization method. Our work showcased the difficulty of finding prognostic biomarkers for a clinical outcome of weak genomic signals, illustrated the benefits of careful study design and data normalization, and provided a practical approach to identify handling effects and select a beneficial normalization method. Our work calls for careful study design and data analysis for the discovery of robust and translatable molecular biomarkers.

Evaluation program for secondary spacecraft cells: Seventeenth annual report of cycle life test

NASA Technical Reports Server (NTRS)

Harkness, J. D.

1981-01-01

Acceptance tests were conducted on nickel cadmium, silver cadmium, and silver zinc cells to insure that all cells put into the life cycle program meet the specifications outlined in the respective purchase contracts. Statistical information is presented on cell performance characteristics and limitations. Weaknesses discovered in cell design are reported and aid in research and development efforts toward improving the reliability of space batteries. Battery weaknesses encountered in satellite programs such as IMP, NIMBUS, OGO, OAO, SAS, and TETR were studied and remedied through special tests.

Storing Data from Qweak--A Precision Measurement of the Proton's Weak Charge

NASA Astrophysics Data System (ADS)

Pote, Timothy

2008-10-01

The Qweak experiment will perform a precision measurement of the proton's parity violating weak charge at low Q-squared. The experiment will do so by measuring the asymmetry in parity-violating electron scattering. The proton's weak charge is directly related to the value of the weak mixing angle--a fundamental quantity in the Standard Model. The Standard Model makes a firm prediction for the value of the weak mixing angle and thus Qweak may provide insight into shortcomings in the SM. The Qweak experiment will run at Thomas Jefferson National Accelerator Facility in Newport News, VA. A database was designed to hold data directly related to the measurement of the proton's weak charge such as detector and beam monitor yield, asymmetry, and error as well as control structures such as the voltage across photomultiplier tubes and the temperature of the liquid hydrogen target. In order to test the database for speed and stability, it was filled with fake data that mimicked the data that Qweak is expected to collect. I will give a brief overview of the Qweak experiment and database design, and present data collected during these tests.

Sense of coherence and diabetes: a prospective occupational cohort study.

PubMed

Kouvonen, Anne M; Väänänen, Ari; Woods, Stephen A; Heponiemi, Tarja; Koskinen, Aki; Toppinen-Tanner, Salla

2008-02-06

Sense of coherence (SOC) is an individual characteristic related to a positive life orientation leading to effective coping. A weak SOC has been associated with indicators of general morbidity and mortality. However, the relationship between SOC and diabetes has not been studied in prospective design. The present study prospectively examined the relationship between a weak SOC and the incidence of diabetes. The relationship between a weak SOC and the incidence of diabetes was investigated among 5827 Finnish male employees aged 18-65 at baseline (1986). SOC was measured by questionnaire survey at baseline. Data on prescription diabetes drugs from 1987 to 2004 were obtained from the Drug Imbursement Register held by the Social Insurance Institution. During the follow-up, 313 cases of diabetes were recorded. A weak SOC was associated with a 46% higher risk of diabetes in participants who had been = <50 years of age on entry into the study. This association was independent of age, education, marital status, psychological distress, self-rated health, smoking status, binge drinking and physical activity. No similar association was observed in older employees. The results suggest that besides focusing on well-known risk factors for diabetes, strengthening SOC in employees of = <50 years of age can also play a role in attempts to tackle increasing rates of diabetes.

Fulfilling the law of a single independent variable and improving the result of mathematical educational research

NASA Astrophysics Data System (ADS)

Pardimin, H.; Arcana, N.

2018-01-01

Many types of research in the field of mathematics education apply the Quasi-Experimental method and statistical analysis use t-test. Quasi-experiment has a weakness that is difficult to fulfil “the law of a single independent variable”. T-test also has a weakness that is a generalization of the conclusions obtained is less powerful. This research aimed to find ways to reduce the weaknesses of the Quasi-experimental method and improved the generalization of the research results. The method applied in the research was a non-interactive qualitative method, and the type was concept analysis. Concepts analysed are the concept of statistics, research methods of education, and research reports. The result represented a way to overcome the weaknesses of quasi-Experiments and T-test. In addition, the way was to apply a combination of Factorial Design and Balanced Design, which the authors refer to as Factorial-Balanced Design. The advantages of this design are: (1) almost fulfilling “the low of single independent variable” so no need to test the similarity of the academic ability, (2) the sample size of the experimental group and the control group became larger and equal; so it becomes robust to deal with violations of the assumptions of the ANOVA test.

Modelling Technique for Demonstrating Gravity Collapse Structures in Jointed Rock.

ERIC Educational Resources Information Center

Stimpson, B.

1979-01-01

Described is a base-friction modeling technique for studying the development of collapse structures in jointed rocks. A moving belt beneath weak material is designed to simulate gravity. A description is given of the model frame construction. (Author/SA)

Investigating Passively Floating and Weakly Swimming Organisms: An Activity for Beginning Marine Education Students.

ERIC Educational Resources Information Center

Schlenker, Richard M.

This document presents the outline of a marine biology science unit designed to introduce students to the study and collection of plankton. Extensive details on plankton collections and a seven-item quiz are included. (SL)

Methodological Considerations in Designing and Evaluating Animal-Assisted Interventions.

PubMed

Stern, Cindy; Chur-Hansen, Anna

2013-02-27

This paper presents a discussion of the literature on animal-assisted interventions and describes limitations surrounding current methodological quality. Benefits to human physical, psychological and social health cannot be empirically confirmed due to the methodological limitations of the existing body of research, and comparisons cannot validly be made across different studies. Without a solid research base animal-assisted interventions will not receive recognition and acceptance as a credible alternative health care treatment. The paper draws on the work of four systematic reviews conducted over April-May 2009, with no date restrictions, focusing exclusively on the use of canine-assisted interventions for older people residing in long-term care. The reviews revealed a lack of good quality studies. Although the literature base has grown in volume since its inception, it predominantly consists of anecdotal accounts and reports. Experimental studies undertaken are often flawed in aspects of design, conduct and reporting. There are few qualitative studies available leading to the inability to draw definitive conclusions. It is clear that due to the complexities associated with these interventions not all weaknesses can be eliminated. However, there are basic methodological weaknesses that can be addressed in future studies in the area. Checklists for quantitative and qualitative research designs to guide future research are offered to help address methodological rigour.

A novel method to fast fix the post OPC weak-points through Calibre eqDRC application

NASA Astrophysics Data System (ADS)

Jin, YaDong; Lyu, Shizhi; Deng, ZeXi; Lu, Cong

2018-03-01

With shrinking nodes, as the layout patterns are becoming more and more complicated, OPC accuracy and performance is becoming increasingly challenging. While we are trying to perfect our OPC script to have a clean output without weak points, in a real urgent tape-out scenario, often there will be weak points and we cannot afford the cost to run the OPC again with an updated OPC recipe. Naturally the post OPC repair becomes the only cost-effective choice. The paper studies and compares a few methods for the post OPC weak-points repair: the manual OPC repair flow and traditional repair flow based on the DRC commands. Here, we introduce a novel method based on the eqDRC commands, which are widely used in the design house but have never been used in the post OPC flow. We discuss how to apply the eqDRC into the post OPC repairs and demonstrate its advantages over the traditional methods.

SWOT analysis: strengths, weaknesses, opportunities and threats of the Israeli Smallpox Revaccination Program.

PubMed

Huerta, Michael; Balicer, Ran D; Leventhal, Alex

2003-01-01

During September 2002, Israel began its current revaccination program against smallpox, targeting previously vaccinated "first responders" among medical and emergency workers. In order to identify the potential strengths and weaknesses of this program and the conditions under which critical decisions were reached, we conducted a SWOT analysis of the current Israeli revaccination program, designed to identify its intrinsic strengths and weaknesses, as well as opportunities for its success and threats against it. SWOT analysis--a practical tool for the study of public health policy decisions and the social and political contexts in which they are reached--revealed clear and substantial strengths and weaknesses of the current smallpox revaccination program, intrinsic to the vaccine itself. A number of threats were identified that may jeopardize the success of the current program, chief among them the appearance of severe complications of vaccination. Our finding of a lack of a generation of knowledge on smallpox vaccination highlights the need for improved physician education and dissipation of misconceptions that are prevalent in the public today.

Understanding thread properties for red blood cell antigen assays: weak ABO blood typing.

PubMed

Nilghaz, Azadeh; Zhang, Liyuan; Li, Miaosi; Ballerini, David R; Shen, Wei

2014-12-24

"Thread-based microfluidics" research has so far focused on utilizing and manipulating the wicking properties of threads to form controllable microfluidic channels. In this study we aim to understand the separation properties of threads, which are important to their microfluidic detection applications for blood analysis. Confocal microscopy was utilized to investigate the effect of the microscale surface morphologies of fibers on the thread's separation efficiency of red blood cells. We demonstrated the remarkably different separation properties of threads made using silk and cotton fibers. Thread separation properties dominate the clarity of blood typing assays of the ABO groups and some of their weak subgroups (Ax and A3). The microfluidic thread-based analytical devices (μTADs) designed in this work were used to accurately type different blood samples, including 89 normal ABO and 6 weak A subgroups. By selecting thread with the right surface morphology, we were able to build μTADs capable of providing rapid and accurate typing of the weak blood groups with high clarity.

Improving the design of maintenance studies for bipolar disorder.

PubMed

Gitlin, Michael J; Abulseoud, Osama; Frye, Mark A

2010-08-01

In contrast to the trial design of acute mania studies, there is no standard design for bipolar maintenance studies. Over the past 15 years, the design of monotherapy maintenance studies in bipolar disorder has evolved significantly, but recent study designs continue to differ in important ways. We reviewed the design of recent controlled bipolar maintenance studies, using PubMed, from August 2006 to August 2009, examining the strengths and weaknesses of different study design features. Design differences are sufficiently important that the disparate results across maintenance studies may reflect either true differences in medication efficacy or the effects of these design differences on outcome. Design elements such as recent episode polarity, stabilization criteria, using enriched versus nonenriched samples, length of stabilization before randomization, length of experimental phase, and recurrence outcome criteria are critical factors that differ widely across studies and likely play a role in study outcome. As consensus for trial designs for bipolar maintenance therapy is developed, it will be easier to develop algorithms for maintenance treatment based on results from studies as opposed to clinical opinions.

The design of preamplifier and ADC circuit base on weak e-optical signal

NASA Astrophysics Data System (ADS)

Fen, Leng; Ying-ping, Yang; Ya-nan, Yu; Xiao-ying, Xu

2011-02-01

Combined with the demand of the process of weak e-optical signal in QPD detection system, the article introduced the circuit principle of deigning preamplifier and ADC circuit with I/V conversion, instrumentation amplifier, low-pass filter and 16-bit A/D transformation. At the same time the article discussed the circuit's noise suppression and isolation according to the characteristics of the weak signal, and gave the method of software rectification. Finally, tested the weak signal with keithley2000, and got a good effect.

Cycle life test. [of secondary spacecraft cells

NASA Technical Reports Server (NTRS)

Harkness, J. D.

1977-01-01

Statistical information concerning cell performance characteristics and limitations of secondary spacecraft cells is presented. Weaknesses in cell design as well as battery weaknesses encountered in various satellite programs are reported. Emphasis is placed on improving the reliability of space batteries.

Performance Optimization Design for a High-Speed Weak FBG Interrogation System Based on DFB Laser.

PubMed

Yao, Yiqiang; Li, Zhengying; Wang, Yiming; Liu, Siqi; Dai, Yutang; Gong, Jianmin; Wang, Lixin

2017-06-22

A performance optimization design for a high-speed fiber Bragg grating (FBG) interrogation system based on a high-speed distributed feedback (DFB) swept laser is proposed. A time-division-multiplexing sensor network with identical weak FBGs is constituted to realize high-capacity sensing. In order to further improve the multiplexing capacity, a waveform repairing algorithm is designed to extend the dynamic demodulation range of FBG sensors. It is based on the fact that the spectrum of an FBG keeps stable over a long period of time. Compared with the pre-collected spectra, the distorted spectra waveform are identified and repaired. Experimental results show that all the identical weak FBGs are distinguished and demodulated at the speed of 100 kHz with a linearity of above 0.99, and the range of dynamic demodulation is extended by 40%.

Performance Optimization Design for a High-Speed Weak FBG Interrogation System Based on DFB Laser

PubMed Central

Yao, Yiqiang; Li, Zhengying; Wang, Yiming; Liu, Siqi; Dai, Yutang; Gong, Jianmin; Wang, Lixin

2017-01-01

A performance optimization design for a high-speed fiber Bragg grating (FBG) interrogation system based on a high-speed distributed feedback (DFB) swept laser is proposed. A time-division-multiplexing sensor network with identical weak FBGs is constituted to realize high-capacity sensing. In order to further improve the multiplexing capacity, a waveform repairing algorithm is designed to extend the dynamic demodulation range of FBG sensors. It is based on the fact that the spectrum of an FBG keeps stable over a long period of time. Compared with the pre-collected spectra, the distorted spectra waveform are identified and repaired. Experimental results show that all the identical weak FBGs are distinguished and demodulated at the speed of 100 kHz with a linearity of above 0.99, and the range of dynamic demodulation is extended by 40%. PMID:28640187

Contrastive Pragmatics of English and Japanese Offers and Requests.

ERIC Educational Resources Information Center

Christianson, Kiel

This paper analyzes a study by Fukushima (1990) of the English offers and responses of Japanese English as a foreign language (EFL) college students and reports on an experiment designed to address the perceived weaknesses of Fukushima's work. Fukushima's study found that many Japanese EFL learners could not use appropriate levels of politeness in…

Correlation of the Rock Mass Rating (RMR) System with the Unified Soil Classification System (USCS): Introduction of the Weak Rock Mass Rating System (W-RMR)

NASA Astrophysics Data System (ADS)

Warren, Sean N.; Kallu, Raj R.; Barnard, Chase K.

2016-11-01

Underground gold mines in Nevada are exploiting increasingly deeper ore bodies comprised of weak to very weak rock masses. The Rock Mass Rating (RMR) classification system is widely used at underground gold mines in Nevada and is applicable in fair to good-quality rock masses, but is difficult to apply and loses reliability in very weak rock mass to soil-like material. Because very weak rock masses are transition materials that border engineering rock mass and soil classification systems, soil classification may sometimes be easier and more appropriate to provide insight into material behavior and properties. The Unified Soil Classification System (USCS) is the most likely choice for the classification of very weak rock mass to soil-like material because of its accepted use in tunnel engineering projects and its ability to predict soil-like material behavior underground. A correlation between the RMR and USCS systems was developed by comparing underground geotechnical RMR mapping to laboratory testing of bulk samples from the same locations, thereby assigning a numeric RMR value to the USCS classification that can be used in spreadsheet calculations and geostatistical analyses. The geotechnical classification system presented in this paper including a USCS-RMR correlation, RMR rating equations, and the Geo-Pick Strike Index is collectively introduced as the Weak Rock Mass Rating System (W-RMR). It is the authors' hope that this system will aid in the classification of weak rock masses and more usable design tools based on the RMR system. More broadly, the RMR-USCS correlation and the W-RMR system help define the transition between engineering soil and rock mass classification systems and may provide insight for geotechnical design in very weak rock masses.

Quasi experimental designs in pharmacist intervention research.

PubMed

Krass, Ines

2016-06-01

Background In the field of pharmacist intervention research it is often difficult to conform to the rigorous requirements of the "true experimental" models, especially the requirement of randomization. When randomization is not feasible, a practice based researcher can choose from a range of "quasi-experimental designs" i.e., non-randomised and at time non controlled. Objective The aim of this article was to provide an overview of quasi-experimental designs, discuss their strengths and weaknesses and to investigate their application in pharmacist intervention research over the previous decade. Results In the literature quasi experimental studies may be classified into five broad categories: quasi-experimental design without control groups; quasi-experimental design that use control groups with no pre-test; quasi-experimental design that use control groups and pre-tests; interrupted time series and stepped wedge designs. Quasi-experimental study design has consistently featured in the evolution of pharmacist intervention research. The most commonly applied of all quasi experimental designs in the practice based research literature are the one group pre-post-test design and the non-equivalent control group design i.e., (untreated control group with dependent pre-tests and post-tests) and have been used to test the impact of pharmacist interventions in general medications management as well as in specific disease states. Conclusion Quasi experimental studies have a role to play as proof of concept, in the pilot phases of interventions when testing different intervention components, especially in complex interventions. They serve to develop an understanding of possible intervention effects: while in isolation they yield weak evidence of clinical efficacy, taken collectively, they help build a body of evidence in support of the value of pharmacist interventions across different practice settings and countries. However, when a traditional RCT is not feasible for logistical and/or ethical reasons researchers should endeavour to use the more robust of the quasi experimental designs.

Improvement for determining the axial capacity of drilled shafts in shale in Illinois.

DOT National Transportation Integrated Search

2013-05-01

In this project, Illinois-specific design procedures were developed for drilled shafts founded in weak shale. In addition, : recommendations for field and laboratory testing to characterize the in situ condition of weak shales in Illinois were : deve...

Influenza Research in the Eastern Mediterranean Region: A Review

PubMed Central

Khan, Wasiq; El Rifay, Amira S.; Malik, Mamun; Kayali, Ghazi

2017-01-01

Given the importance of influenza infections in the Eastern Mediterranean Region (EMR), we conducted a comprehensive literature review to analyze the status of influenza research in the region from 2012. Influenza research has gained more momentum recently with the emergence of H5N1 and new virus strains. Research covering epidemiological, veterinary, and basic science aspects is growing. More sequences were being generated per year, not only for diagnostic purposes but also for research. We included gray literature publications in our search and found several graduate student dissertations from Egypt, which were published on an online portal. However, the search revealed some weaknesses, mostly in the areas of study design and the lack of surveillance studies. Another weakness was the fact that the publications originated from very few countries, mainly Egypt and Iran. Although improving, influenza research in the EMR remains weak. We recommend encouraging countries in the EMR to conduct more influenza research using stronger methodologies. PMID:29026466

Magic Mirror, On the Wall-Which Is the Right Study Design of Them All?-Part II.

PubMed

Vetter, Thomas R

2017-07-01

The assessment of a new or existing treatment or other intervention typically answers 1 of 3 central research-related questions: (1) "Can it work?" (efficacy); (2) "Does it work?" (effectiveness); or (3) "Is it worth it?" (efficiency or cost-effectiveness). There are a number of study designs that, on a situational basis, are appropriate to apply in conducting research. These study designs are generally classified as experimental, quasiexperimental, or observational, with observational studies being further divided into descriptive and analytic categories. This second of a 2-part statistical tutorial reviews these 3 salient research questions and describes a subset of the most common types of observational study designs. Attention is focused on the strengths and weaknesses of each study design to assist in choosing which is appropriate for a given study objective and hypothesis as well as the particular study setting and available resources and data. Specific studies and papers are highlighted as examples of a well-chosen, clearly stated, and properly executed study design type.

Magic Mirror, on the Wall-Which Is the Right Study Design of Them All?-Part I.

PubMed

Vetter, Thomas R

2017-06-01

The assessment of a new or existing treatment or intervention typically answers 1 of 3 research-related questions: (1) "Can it work?" (efficacy); (2) "Does it work?" (effectiveness); and (3) "Is it worth it?" (efficiency or cost-effectiveness). There are a number of study designs that on a situational basis are appropriate to apply in conducting research. These study designs are classified as experimental, quasi-experimental, or observational, with observational studies being further divided into descriptive and analytic categories. This first of a 2-part statistical tutorial reviews these 3 salient research questions and describes a subset of the most common types of experimental and quasi-experimental study design. Attention is focused on the strengths and weaknesses of each study design to assist in choosing which is appropriate for a given study objective and hypothesis as well as the particular study setting and available resources and data. Specific studies and papers are highlighted as examples of a well-chosen, clearly stated, and properly executed study design type.

College Success Courses: Success for All

ERIC Educational Resources Information Center

Coleman, Sandra Lee; Skidmore, Susan Troncoso; Weller, Carol Thornton

2018-01-01

College success courses (CSCs), or orientation courses, are offered by community colleges and universities to facilitate the success of first-time-in-college students. Primarily, these courses are designed to address students' nonacademic deficiencies, such as weak study habits and poor organizational skills, and to familiarize students with…

A Framework for Understanding Community Colleges' Organizational Capacity for Data Use: A Convergent Parallel Mixed Methods Study

ERIC Educational Resources Information Center

Kerrigan, Monica Reid

2014-01-01

This convergent parallel design mixed methods case study of four community colleges explores the relationship between organizational capacity and implementation of data-driven decision making (DDDM). The article also illustrates purposive sampling using replication logic for cross-case analysis and the strengths and weaknesses of quantitizing…

Weak Interactions Group

Science.gov Websites

Weak Interactions Group UC Berkeley UC Berkeley Physics Lawrence Berkeley Lab Nuclear Science Division at LBL Physics Division at LBL Phonebook A-Z Index Navigation Home Members Research Projects CUORE Design Concept Berkeley Projects People Publications Contact Links KamLAND Physics Impact Neutrino

Toward a More Flexible Web-Based Framework for Multidisciplinary Design

NASA Technical Reports Server (NTRS)

Rogers, J. L.; Salas, A. O.

1999-01-01

In today's competitive environment, both industry and government agencies are under pressure to reduce the time and cost of multidisciplinary design projects. New tools have been introduced to assist in this process by facilitating the integration of and communication among diverse disciplinary codes. One such tool, a framework for multidisciplinary design, is defined as a hardware-software architecture that enables integration, execution, and communication among diverse disciplinary processes. An examination of current frameworks reveals weaknesses in various areas, such as sequencing, monitoring, controlling, and displaying the design process. The objective of this research is to explore how Web technology can improve these areas of weakness and lead toward a more flexible framework. This article describes a Web-based system that optimizes and controls the execution sequence of design processes in addition to monitoring the project status and displaying the design results.

Guidelines for pre-clinical assessment of the acetylcholine receptor-specific passive transfer myasthenia gravis model - recommendations for methods and experimental designs

PubMed Central

Kusner, Linda L.; Losen, Mario; Vincent, Angela; Lindstrom, Jon; Tzartos, Socrates; Lazaridis, Konstantinos; Martinez-Martinez, Pilar

2015-01-01

Antibodies against the muscle acetylcholine receptor (AChR) are the most common cause of myasthenia gravis (MG). Passive transfer of AChR antibodies from MG patients into animals reproduces key features of human disease, including antigenic modulation of the AChR, complement-mediated damage of the neuromuscular junction, and muscle weakness. Similarly, AChR antibodies generated by active immunization in experimental autoimmune MG models can subsequently be passively transferred to other animals and induce weakness. The passive transfer model is useful to test therapeutic strategies aimed at the effector mechanism of the autoantibodies. Here we summarize published and unpublished experience using the AChR passive transfer MG model in mice, rats and rhesus monkeys, and give recommendations for the design of preclinical studies in order to facilitate translation of positive and negative results to improve MG therapies. PMID:25743217

Design of control-group conditions in clinical trials of behavioral interventions.

PubMed

Lindquist, Ruth; Wyman, Jean F; Talley, Kristine M C; Findorff, Mary J; Gross, Cynthia R

2007-01-01

To review considerations in the design of placebo (attention) control conditions for community-based clinical trials of health behavior change interventions and to provide practical strategies for the design of control conditions. A well-designed control condition is an essential component of a clinical trial to foster the unambiguous interpretation of study findings. Pitfalls in the design of control conditions in clinical trials of behavioral interventions are identified and strategies to address them are offered. Types of control conditions that have been used in fall prevention trials are described, along with their strengths and weaknesses. The control condition used in the recent fall evaluation and prevention program (FEPP) was designed to overcome limitations of previous trial designs; it is provided to illustrate how to apply specific design principles. Pitfalls in the design of behavioral intervention studies may be avoided with the application of sound design principles. The FEPP active control condition can be used as a model in the design of future studies.

Impact Evaluation of Service Programs: Three Flexible Designs.

ERIC Educational Resources Information Center

McKillip, Jack

1979-01-01

Flexibility in evaluative research design does not necessitate the abandonment of randomly constructed comparison groups. Three designs are reviewed which provide at least the option of randomization while maintaining great flexibility. The strengths and weaknesses of the designs are discussed. (Author)

Comparing three sampling techniques for estimating fine woody down dead biomass

Treesearch

Robert E. Keane; Kathy Gray

2013-01-01

Designing woody fuel sampling methods that quickly, accurately and efficiently assess biomass at relevant spatial scales requires extensive knowledge of each sampling method's strengths, weaknesses and tradeoffs. In this study, we compared various modifications of three common sampling methods (planar intercept, fixed-area microplot and photoload) for estimating...

Geography Students Assess Their Learning Using Computer-Marked Tests.

ERIC Educational Resources Information Center

Hogg, Jim

1997-01-01

Reports on a pilot study designed to assess the potential of computer-marked tests for allowing students to monitor their learning. Students' answers to multiple choice tests were fed into a computer that provided a full analysis of their strengths and weaknesses. Students responded favorably to the feedback. (MJP)

Science Labs: Beyond Isolationism

ERIC Educational Resources Information Center

Cavanagh, Sean

2007-01-01

A national study released in 2005 concluded that most high school students are not exposed to high quality science labs because of these reasons: (a) poor school facilities and organizations; (b) weak teacher preparation; (c) poor design; (d) cluttered state standards; (e) little representation on state tests; and (f) scarce evidence of what…

Oral History as a Motivating Factor among Adult Learners.

ERIC Educational Resources Information Center

Lawrence, Janet H.; Lehman, Esther

An exploratory study was designed to assess (1) whether a class created around older adults' personal recollections would motivate the class's involvement in adult education activities, (2) the oral history preparation process's impact on younger interviewers and older respondents, and (3) the instructional approach's strengths and weaknesses. The…

Endogenous Cortical Oscillations Constrain Neuromodulation by Weak Electric Fields

PubMed Central

Schmidt, Stephen L.; Iyengar, Apoorva K.; Foulser, A. Alban; Boyle, Michael R.; Fröhlich, Flavio

2014-01-01

Background Transcranial alternating current stimulation (tACS) is a non-invasive brain stimulation modality that may modulate cognition by enhancing endogenous neocortical oscillations with the application of sine-wave electric fields. Yet, the role of endogenous network activity in enabling and shaping the effects of tACS has remained unclear. Objective We combined optogenetic stimulation and multichannel slice electrophysiology to elucidate how the effect of weak sine-wave electric field depends on the ongoing cortical oscillatory activity. We hypothesized that the structure of the response to stimulation depended on matching the stimulation frequency to the endogenous cortical oscillation. Methods We studied the effect of weak sine-wave electric fields on oscillatory activity in mouse neocortical slices. Optogenetic control of the network activity enabled the generation of in vivo like cortical oscillations for studying the temporal relationship between network activity and sine-wave electric field stimulation. Results Weak electric fields enhanced endogenous oscillations but failed to induce a frequency shift of the ongoing oscillation for stimulation frequencies that were not matched to the endogenous oscillation. This constraint on the effect of electric field stimulation imposed by endogenous network dynamics was limited to the case of weak electric fields targeting in vivo-like network dynamics. Together, these results suggest that the key mechanism of tACS may be enhancing but not overriding of intrinsic network dynamics. Conclusion Our results contribute to understanding the inconsistent tACS results from human studies and propose that stimulation precisely adjusted in frequency to the endogenous oscillations is key to rational design of non-invasive brain stimulation paradigms. PMID:25129402

107: REVIEW OF THE QUALITY HOSPITALS WEBSITES IN KHORASAN RAZAVI PROVINCE

PubMed Central

Dastani, Meisam; Sattari, Masoume

2017-01-01

Background and aims The aim of the present study is to present a clear vision of the quality status of Khorasan Razavi hospitals websites in four dimensions of content, performance, management and usage of the website. Methods This is a survey study. The sample consisted of 49 hospital websites of Khorasan Razavi province. The instrument was used check list including 21 components and four criteria (content, performance, management and how to use the website). Its validity and reliability have proved through previous studies. Also, the data were analyzed using descriptive statistics. Results The findings showed that only %59 of hospitals in Khorasan Razavi, has been active website. The overall Status of website showed that the most popular websites of the situation, too weak (%51), moderate (%26.5) and weak (%16.3), respectively. In relation to criteria content, study, management and how to usage of the website and design, the findings showed that %40.8 of websites had an unfavorable condition. Of the 16 high quality website selected, only three websites Sina Hospital in Mashhad, Javdoll-Aemeh in Mashhad and Razavi were in good condition and the other of the websites had weak condition. Conclusion The results of this study indicate that, yet most websites do not regard minimal medical standards and also, they could not establish good relationships with their audiences. In fact, in Iran, still regard to the quality and performance of websites has not been one of the priorities for improving service quality in hospitals. The findings of this study can be effective in the identification and development of hospital websites quality criteria in terms of design, content, performance and management and how to use.

How Programme Teams Progress Agricultural Innovation in the Australian Dairy Industry

ERIC Educational Resources Information Center

Nettle, Ruth; Brightling, Pauline; Hope, Anne

2013-01-01

Purpose: This article outlines the emergence of programme teams in the Australian dairy farm sector as a response to counter weaknesses in the institutional environment for agricultural innovation which favours technology adoption/diffusion approaches. Design/methodology/approach: The strengths, weaknesses and risks of different approaches to…

Electrical coupled Morris-Lecar neurons: From design to pattern analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Binczak, S.; Behdad, R.; Rossé, M.

2016-06-08

In this study, an experimental electronic neuron based on Morris-Lecar model is presented, able to become an experimental unit tool to study collective association of robust coupled neurons. The circuit design is given according to the ionic currents of this model. A weak coupling of such neurons under Multisim Software can generate clusters based on the boundary conditions of the neurons and their initial conditions. For this study, we work in the region close to the fold bifurcation of limit cycles. In this region two limit cycles exist, one of the cycles is stable and another one is unstable.

Designing with Only Four People in Mind? - A Case Study of Using Personas to Redesign a Work-Integrated Learning Support System

NASA Astrophysics Data System (ADS)

Dotan, Amir; Maiden, Neil; Lichtner, Valentina; Germanovich, Lola

In this paper we describe and reflect on the use of personas to redesign the 3rd prototype of APOSDLE - a system to support informal learning and knowledge transfer in the workplace. Based on the results of a formative evaluation of the 2nd prototype we used personas to explore how users’ goals, behaviour and preferences could be communicated to project members during a two-day design workshop, in order to ensure useful and usable design solutions. We actively involved stakeholders representing the target market throughout the process as they helped to create, validate and interpret the four personas we used. By doing so we aimed to address methodological weaknesses and practical limitations of using personas, primarily those relating to the validity of the personas used and the way they are interpreted. We reflected on how effective the personas were by referring to data generated during the workshop and discussion transcripts. As reported by others, and as we have experienced ourselves, using personas can be quite challenging as rich narrative descriptions are expected to produce insight and design solutions. In light of this challenge, we contribute a case study illustrating how personas were implemented in a real world situation to engage project members with user information and drive the design process. We specifically discussed the strengths and weaknesses of actively involving stakeholders in creating and using personas.

A Program Based on the Pragmatic Theory to Develop Grammatical Structure Comprehension Skills for Foreign Learners of Arabic

ERIC Educational Resources Information Center

Elsamman, Marwan

2014-01-01

This study aimed at designing a program based on the Pragmatic theory to develop grammatical structure comprehension skills for foreign learners of Arabic and examining its effectiveness. Hence, the problem of the study has been summarized in the weakness of grammatical structure comprehension skills for foreign learners of Arabic and in the need…

Re-Using of the Historical Buildings in the Context of Sustainablity: AN Architectural Design Studio Study on Old Girls Teacher Training School

NASA Astrophysics Data System (ADS)

Ulusoy, M.; Erdogan, E.; Erdogan, H. A.; Oral, M.

2013-07-01

Refunctioning is a widely used method for protecting historical structures. However, throughout architectural education, functioning historical structures and producing new designs in terms of historical pattern do not attract great attention within the framework of design studios. It is a fact that in such schools that abovementioned items are more popular, the connection between protection oriented studio and design studio is pretty weak. In this study refunctioning was discussed as a design studio topic in relation to the old girls' teacher training school and its immediate surroundings. The primary objective of this design studio is to increase architecture students' awareness in terms of visual and perceptual levels of project designs in historical patterns. Within the context of this manuscript, the experiences gained during design studio process were transferred and discussed.

STRengthening Analytical Thinking for Observational Studies: the STRATOS initiative

PubMed Central

Sauerbrei, Willi; Abrahamowicz, Michal; Altman, Douglas G; le Cessie, Saskia; Carpenter, James

2014-01-01

The validity and practical utility of observational medical research depends critically on good study design, excellent data quality, appropriate statistical methods and accurate interpretation of results. Statistical methodology has seen substantial development in recent times. Unfortunately, many of these methodological developments are ignored in practice. Consequently, design and analysis of observational studies often exhibit serious weaknesses. The lack of guidance on vital practical issues discourages many applied researchers from using more sophisticated and possibly more appropriate methods when analyzing observational studies. Furthermore, many analyses are conducted by researchers with a relatively weak statistical background and limited experience in using statistical methodology and software. Consequently, even ‘standard’ analyses reported in the medical literature are often flawed, casting doubt on their results and conclusions. An efficient way to help researchers to keep up with recent methodological developments is to develop guidance documents that are spread to the research community at large. These observations led to the initiation of the strengthening analytical thinking for observational studies (STRATOS) initiative, a large collaboration of experts in many different areas of biostatistical research. The objective of STRATOS is to provide accessible and accurate guidance in the design and analysis of observational studies. The guidance is intended for applied statisticians and other data analysts with varying levels of statistical education, experience and interests. In this article, we introduce the STRATOS initiative and its main aims, present the need for guidance documents and outline the planned approach and progress so far. We encourage other biostatisticians to become involved. PMID:25074480

Study on the strength characteristics of High strength concrete with Micro steel fibers

NASA Astrophysics Data System (ADS)

Gowdham, K.; Sumathi, A.; Saravana Raja Mohan, K.

2017-07-01

The study of High Strength Concrete (HSC) has become interesting as concrete structures grow taller and larger. The usage of HSC in structures has been increased worldwide and has begun to make an impact in India. Ordinary cementitious materials are weak under tensile loads and fiber reinforced cementitious composites (FRCCs) have been developed to improve this weak point. High Strength concrete containing Alccofine as mineral admixture and reinforced with micro steel fibers were cast and tested to study the mechanical properties. The concrete were designed to have compressive strength of 60 MPa. Mixtures containing 0% and 10% replacement of cement by Alccofine and with 1%, 2% and 3% of micro steel fibers by weight of concrete were prepared. Mixtures incorporating Alccofine with fibers developed marginal increase in strength properties at all curing days when compared to control concrete.

School Leadership, Social Justice and Immigration: Examining, Exploring and Extending Two Frameworks

ERIC Educational Resources Information Center

Brooks, Jeffrey S.; Normore, Anthony H.; Wilkinson, Jane

2017-01-01

Purpose: The purpose of this paper is to explore theoretical connections between educational leadership for social justice and support for immigration. The authors seek to identify strengths, weaknesses and opportunities for further study and improved practice. Design/methodology/approach: This is a theoretical research paper that introduces,…

Planned Change in Teacher Education: Unfreezing the Status Quo through the Integration of Technology.

ERIC Educational Resources Information Center

Bell, Edwin D.; Ireh, Madu

This study examined planned change in Winston-Salem State University's teacher education program. An external review of the School of Education indicated a weakness in program planning and curriculum design. This review stimulated planned change initiative to strengthen teacher education. Factors influencing the internal environment of teacher…

Library Web Sites in Pakistan: An Analysis of Content

ERIC Educational Resources Information Center

Qutab, Saima; Mahmood, Khalid

2009-01-01

Purpose: The purpose of this paper is to investigate library web sites in Pakistan, to analyse their content and navigational strengths and weaknesses and to give recommendations for developing better web sites and quality assessment studies. Design/methodology/approach: Survey of web sites of 52 academic, special, public and national libraries in…

A Study on the Perceived Risk of Surface Sample Collection Systems in Proposal Formulation

NASA Technical Reports Server (NTRS)

Sunday, Cecily M.

2012-01-01

This project compares design and proposal elements from multiple proposals and presents conclusions and recommendations for sampling systems. Contributions from this project include a list of common evaluation themes, concept and proposal-related strengths and weaknesses and ways in which self-identified risks relate the evaluation of the mission.

Development of socketed foundations for S3X5.7 posts.

DOT National Transportation Integrated Search

2015-04-01

The objective of this study was to develop a socketed foundation for use with the S3x5.7 (S76x8.5) weak : post. The design focused on cylindrical, reinforced concrete foundations with a steel tube placed in the center for : use as the socket. The fou...

Exploring Prospective Teachers' Reflections in the Context of Conducting Clinical Interviews

ERIC Educational Resources Information Center

Taylan, Rukiye Didem

2018-01-01

This study investigated prospective mathematics teachers' reflections on the experience of designing and conducting one-to-one clinical interviews with middle school students in the context of an elective course on use of video in teacher learning. Prospective teachers were asked to write about weaknesses and strengths in student understanding as…

The Miles College Freshman Social Science Program: Educational Innovation in a Negro College

ERIC Educational Resources Information Center

Friedman, Neil

1969-01-01

Study supported by Tuskegee Institute Division of Behavioral Science Research. Describes the content and outcome of a program of historical and political education designed to avoid the academic weaknesses and exploit the strengths of Black college freshmen, and to foster an attitude of racial pride in them. (JM)

Invented Rule with English Language Learners

ERIC Educational Resources Information Center

Boyer, Valerie E.; Martin, Kathryn Y.

2012-01-01

The purpose of this study was to utilize an invented rule with English language learners (ELLs) in a clinical setting to determine differences based on language and age of the children. The performance was correlated with teacher reports of strong and weak language learning. Using a within-participants design, ELLs of age three to five were taught…

Students with Low Vision Describe Their Visual Impairments and Visual Functioning

ERIC Educational Resources Information Center

Guerette, Amy R.; Lewis, Sandra; Mattingly, Cameron

2011-01-01

In the study reported here, the responses to a survey that was designed to determine the knowledge of their visual impairment of 51 students with low vision were analyzed. Although the students described their visual weaknesses and strengths, they had limited knowledge of, and difficulty communicating about, the medical aspects of their…

In-situ evaluation of design parameters and procedures for cementitiously treated weak subgrades using cyclic plate load tests : project capsule.

DOT National Transportation Integrated Search

2013-06-01

Due to the soft nature of subsurface soils in southern Louisiana, roads often have to : be constructed on very weak subgrade soils with high in-situ moisture contents that : do not have the suffi cient strength/stiff ness to support the construction/...

SWOT analysis for safer carriage of bulk liquid chemicals in tankers.

PubMed

Arslan, Ozcan; Er, Ismail Deha

2008-06-15

The application of strengths, weaknesses, opportunities and threats (SWOT) analysis to formulation of strategy concerned with the safe carriage of bulk liquid chemicals in maritime tankers was examined in this study. A qualitative investigation using SWOT analysis has been implemented successfully for ships that are designed to carry liquid chemicals in bulk. The originality of this study lies in the use of SWOT analysis as a management tool to formulate strategic action plans for ship management companies, ship masters and officers for the carriage of dangerous goods in bulk. With this transportation-based SWOT analysis, efforts were made to explore the ways and means of converting possible threats into opportunities, and changing weaknesses into strengths; and strategic plans of action were developed for safer tanker operation.

The patient safety culture: a systematic review by characteristics of Hospital Survey on Patient Safety Culture dimensions.

PubMed

Reis, Cláudia Tartaglia; Paiva, Sofia Guerra; Sousa, Paulo

2018-05-08

To learn the weaknesses and strengths of safety culture as expressed by the dimensions measured by the Hospital Survey on Patient Safety Culture (HSOPSC) at hospitals in the various cultural contexts. The aim of this study was to identify studies that have used the HSOPSC to collect data on safety culture at hospitals; to survey their findings in the safety culture dimensions and possible contributions to improving the quality and safety of hospital care. Medline (via PubMed), Web of Science and Scopus were searched from 2005 to July 2016 in English, Portuguese and Spanish. Studies were identified using specific search terms and inclusion criteria. A total of 33 articles, reporting on 21 countries, was included. Scores were extracted by patient safety culture dimensions assessed by the HSOPSC. The quality of the studies was evaluated by the STROBE Statement. The dimensions that proved strongest were 'Teamwork within units' and 'Organisational learning-continuous improvement'. Particularly weak dimensions were 'Non-punitive response to error', 'Staffing', 'Handoffs and transitions' and 'Teamwork across units'. The studies revealed a predominance of hospital organisational cultures that were underdeveloped or weak as regards patient safety. For them to be effective, safety culture evaluation should be tied to strategies designed to develop safety culture hospital-wide.

Tunable Fano resonance using weak-value amplification with asymmetric spectral response as a natural pointer

NASA Astrophysics Data System (ADS)

Singh, Ankit K.; Ray, Subir K.; Chandel, Shubham; Pal, Semanti; Gupta, Angad; Mitra, P.; Ghosh, N.

2018-05-01

Weak measurement enables faithful amplification and high-precision measurement of small physical parameters and is under intensive investigation as an effective tool in metrology and for addressing foundational questions in quantum mechanics. Here we demonstrate weak-value amplification using the asymmetric spectral response of Fano resonance as the pointer arising naturally in precisely designed metamaterials, namely, waveguided plasmonic crystals. The weak coupling between the polarization degree of freedom and the spectral response of Fano resonance arises due to a tiny shift in the asymmetric spectral response between two orthogonal linear polarizations. By choosing the preselected and postselected polarization states to be nearly mutually orthogonal, we observe both real and imaginary weak-value amplifications manifested as a spectacular shift of the Fano-resonance peak and narrowing (or broadening) of the resonance linewidth, respectively. The remarkable control and tunability of Fano resonance in a single device enabled by weak-value amplification may enhance active Fano-resonance-based applications in the nano-optical domain. In general, weak measurements using Fano-type spectral response broadens the domain of applicability of weak measurements using natural spectral line shapes as a pointer in a wide range of physical systems.

30 CFR 75.310 - Installation of main mine fans.

Code of Federal Regulations, 2011 CFR

2011-07-01

... that gives a signal at the mine when the fan either slows or stops. A responsible person designated by the operator shall always be at a surface location at the mine where the signal can be seen or heard... weak walls or explosion doors, or a combination of weak walls and explosion doors, located in direct...

30 CFR 75.310 - Installation of main mine fans.

Code of Federal Regulations, 2010 CFR

2010-07-01

... that gives a signal at the mine when the fan either slows or stops. A responsible person designated by the operator shall always be at a surface location at the mine where the signal can be seen or heard... weak walls or explosion doors, or a combination of weak walls and explosion doors, located in direct...

30 CFR 75.310 - Installation of main mine fans.

Code of Federal Regulations, 2013 CFR

2013-07-01

... that gives a signal at the mine when the fan either slows or stops. A responsible person designated by the operator shall always be at a surface location at the mine where the signal can be seen or heard... weak walls or explosion doors, or a combination of weak walls and explosion doors, located in direct...

30 CFR 75.310 - Installation of main mine fans.

Code of Federal Regulations, 2012 CFR

2012-07-01

... that gives a signal at the mine when the fan either slows or stops. A responsible person designated by the operator shall always be at a surface location at the mine where the signal can be seen or heard... weak walls or explosion doors, or a combination of weak walls and explosion doors, located in direct...

30 CFR 75.310 - Installation of main mine fans.

Code of Federal Regulations, 2014 CFR

2014-07-01

... that gives a signal at the mine when the fan either slows or stops. A responsible person designated by the operator shall always be at a surface location at the mine where the signal can be seen or heard... weak walls or explosion doors, or a combination of weak walls and explosion doors, located in direct...

Design and Discovery of Functionally Selective Serotonin 2C (5-HT2C) Receptor Agonists.

PubMed

Cheng, Jianjun; McCorvy, John D; Giguere, Patrick M; Zhu, Hu; Kenakin, Terry; Roth, Bryan L; Kozikowski, Alan P

2016-11-10

On the basis of the structural similarity of our previous 5-HT 2C agonists with the melatonin receptor agonist tasimelteon and the putative biological cross-talk between serotonergic and melatonergic systems, a series of new (2,3-dihydro)benzofuran-based compounds were designed and synthesized. The compounds were evaluated for their selectivity toward 5-HT 2A , 5-HT 2B , and 5-HT 2C receptors in the calcium flux assay with the ultimate goal to generate selective 5-HT 2C agonists. Selected compounds were studied for their functional selectivity by comparing their transduction efficiency at the G protein signaling pathway versus β-arrestin recruitment. The most functionally selective compound (+)-7e produced weak β-arrestin recruitment and also demonstrated less receptor desensitization compared to serotonin in both calcium flux and phosphoinositide (PI) hydrolysis assays. We report for the first time that selective 5-HT 2C agonists possessing weak β-arrestin recruitment can produce distinct receptor desensitization properties.

Guidelines for pre-clinical assessment of the acetylcholine receptor--specific passive transfer myasthenia gravis model-Recommendations for methods and experimental designs.

PubMed

Kusner, Linda L; Losen, Mario; Vincent, Angela; Lindstrom, Jon; Tzartos, Socrates; Lazaridis, Konstantinos; Martinez-Martinez, Pilar

2015-08-01

Antibodies against the muscle acetylcholine receptor (AChR) are the most common cause of myasthenia gravis (MG). Passive transfer of AChR antibodies from MG patients into animals reproduces key features of human disease, including antigenic modulation of the AChR, complement-mediated damage of the neuromuscular junction, and muscle weakness. Similarly, AChR antibodies generated by active immunization in experimental autoimmune MG models can subsequently be passively transferred to other animals and induce weakness. The passive transfer model is useful to test therapeutic strategies aimed at the effector mechanism of the autoantibodies. Here we summarize published and unpublished experience using the AChR passive transfer MG model in mice, rats and rhesus monkeys, and give recommendations for the design of preclinical studies in order to facilitate translation of positive and negative results to improve MG therapies. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Beam Design and User Scheduling for Nonorthogonal Multiple Access With Multiple Antennas Based on Pareto Optimality

NASA Astrophysics Data System (ADS)

Seo, Junyeong; Sung, Youngchul

2018-06-01

In this paper, an efficient transmit beam design and user scheduling method is proposed for multi-user (MU) multiple-input single-output (MISO) non-orthogonal multiple access (NOMA) downlink, based on Pareto-optimality. The proposed beam design and user scheduling method groups simultaneously-served users into multiple clusters with practical two users in each cluster, and then applies spatical zeroforcing (ZF) across clusters to control inter-cluster interference (ICI) and Pareto-optimal beam design with successive interference cancellation (SIC) to two users in each cluster to remove interference to strong users and leverage signal-to-interference-plus-noise ratios (SINRs) of interference-experiencing weak users. The proposed method has flexibility to control the rates of strong and weak users and numerical results show that the proposed method yields good performance.

The Model of Interpersonal Teacher Behaviour: A Qualitative Cross-Cultural Validation within the Greek Elementary Education Context

ERIC Educational Resources Information Center

Charalampous, Kyriakos; Kokkinos, Constantinos M.

2013-01-01

The Model of Interpersonal Teacher Behaviour (MITB) provides a widely acclaimed framework for studying the student-teacher interaction. However, the consistently weak psychometric properties of the instruments designed to measure the MITB in educational contexts other than the ones for which the MITB was originally developed, indicate the need for…

Environmental Management Systems for Educational Institutions: A Case Study of Teri University, New Delhi

ERIC Educational Resources Information Center

Jain, Suresh; Pant, Pallavi

2010-01-01

Purpose: The purpose of this paper is to put forth a model for implementation of an environmental management system (EMS) in institutes of higher education in India. Design/methodology/approach: The authors carried out initial environmental review (IER) and strengths, weaknesses, opportunities and threats (SWOT) analysis to identify the major…

Latin America: A Filmic Approach. Latin American Studies Program, Film Series No. 1.

ERIC Educational Resources Information Center

Campbell, Leon G.; And Others

This document describes a university course designed to provide an historical understanding of Latin America through feature films. The booklet contains an introductory essay on the teaching of a film course on Latin America, a general discussion of strengths and weaknesses of student analyses of films, and nine analyses written by students during…

Using Wikis and Blogs for Assessment in First-Year Engineering

ERIC Educational Resources Information Center

Smith, Elizabeth Joy; Mills, Julie Evelyn; Myers, Baden

2009-01-01

Purpose: This paper aims to examine some of the strengths and weaknesses of the use of online tools such as wikis and blogs for assessment purposes, with the aim of proposing future developments and improvements. Design/methodology/approach: The paper utilises a case study approach by examining the outcomes of a new first-year course for all…

On Being in Charge: A Guide to Management in Primary Health Care. Second Edition.

ERIC Educational Resources Information Center

McMahon, Rosemary; And Others

This revised training guide is designed to help health workers, including nurses, midwives, and medical assistants, improve managerial skills. The book is divided into four main parts, each dealing with a different aspect of management. An opening exercise helps readers diagnose managerial weaknesses and turn to appropriate chapters for study.…

Strengths weaknesses opportunities and threats of blended learning: students' perceptions.

PubMed

Hande, S

2014-05-01

Blended learning (BL) in a cell biology course of the premedical program at the Kasturba Medical College International Centre, Manipal, India, commenced in 2006. The program provides training in basic sciences to students, especially from the United States and Canada. The approach to the study was phenomenographic, with a qualitative study design using an open-ended questionnaire, focused interviews and empirical observations. The aim of this study was to identify the strengths, weaknesses, opportunities and threats (SWOT) of BL in a premedical class. It was a cross-sectional study. Ninety six students in a premedical cell biology class participated in the study. SWOT analysis of students' perceptions was conducted manually. Statistical analysis included content analysis of qualitative data to classify data and aligning them into the SWOT analysis matrix. The outcomes of the study revealed student perceptions in terms of SWOT of BL and the potential uses of this strategy. The study provides background for educators and curriculum experts to plan their modules while incorporating a BL approach.

Learning from an Unsuccessful Study Idea: Reflection and Application of Innovative Techniques to Prevent Future Failures.

PubMed

Fujihara, Yuki; Saito, Taichi; Huetteman, Helen E; Sterbenz, Jennifer M; Chung, Kevin C

2018-04-01

A well-organized, thoughtful study design is essential for creating an impactful study. However, pressures promoting high output from researchers can lead to rushed study proposals that overlook critical weaknesses in the study design that can affect the validity of the conclusions. Researchers can benefit from thorough review of past failed proposals when crafting new research ideas. Conceptual frameworks and root cause analysis are two innovative techniques that can be used during study development to identify flaws and prevent study failures. In addition, conceptual frameworks and root cause analysis can be combined to complement each other to provide both a big picture and detailed view of a study proposal. This article describes these two common analytical methods and provides an example of how they can be used to evaluate and improve a study design by critically examining a previous failed research idea.

Development of recommended resistance factors for drilled shafts in weak rocks based on o-cell tests.

DOT National Transportation Integrated Search

2010-03-01

From October 1, 2007, the new bridges on federal-aid funded projects are mandated to be designed to meet : American Association of State Highway and Transportation Officials (AASHTO) Load and Resistance Factor Design : (LRFD) Bridge Design Specificat...

Design of stereoelectronically promoted super lewis acids and unprecedented chemistry of their complexes.

PubMed

Foroutan-Nejad, Cina; Vicha, Jan; Marek, Radek

2014-09-01

A new family of stereoelectronically promoted aluminum and scandium super Lewis acids is introduced on the basis of state-of-the-art computations. Structures of these molecules are designed to minimize resonance electron donation to central metal atoms in the Lewis acids. Acidity of these species is evaluated on the basis of their fluoride-ion affinities relative to the antimony pentafluoride reference system. It is demonstrated that introduced changes in the stereochemistry of the designed ligands increase acidity considerably relative to Al and Sc complexes with analogous monodentate ligands. The high stability of fluoride complexes of these species makes them ideal candidates to be used as weakly coordinating anions in combination with highly reactive cations instead of conventional Lewis acid-fluoride complexes. Further, the interaction of all designed molecules with methane is investigated. All studied acids form stable pentavalent-carbon complexes with methane. In addition, interactions of the strongest acid of this family with very weak bases, namely, H2, N2, carbon oxides, and noble gases were investigated; it is demonstrated that this compound can form considerably stable complexes with the aforementioned molecules. To the best of our knowledge, carbonyl and nitrogen complexes of this species are the first hypothetical four-coordinated carbonyl and nitrogen complexes of aluminum. The nature of bonding in these systems is studied in detail by various bonding analysis approaches. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Increased Patient Cost-Sharing, Weak US Economy, and Poor Health Habits: Implications for Employers and Insurers.

PubMed

Haren, Melinda C; McConnell, Kirk; Shinn, Arthur F

2009-04-01

Many healthcare stakeholders, including insurers and employers, agree that growth in healthcare costs is inevitable. But the current trend toward further cost-shifting to employees and other health plan members is unsustainable. In 2008, the Zitter Group conducted a large national study on the relationship between insurers and employers, to understand how these 2 healthcare stakeholders interact in the creation of health benefit design. The survey results were previously summarized and discussed in the February/March 2009 issue of this journal. The present article aims to assess the implications of those results in the context of the growing tendency to increase patient cost-sharing, a weak US economy, and poor health habits. Increasing cost-sharing is a blunt instrument: although it may reduce utilization of frivolous services, it may also result in individuals forgoing medically necessary care. Increases in deductibles will lead to an overall decrease in optimal care-seeking behavior as families juggle healthcare costs with a weak economy and stagnating wages.

Boiling points of halogenated ethanes: an explanatory model implicating weak intermolecular hydrogen-halogen bonding.

PubMed

Beauchamp, Guy

2008-10-23

This study explores via structural clues the influence of weak intermolecular hydrogen-halogen bonds on the boiling point of halogenated ethanes. The plot of boiling points of 86 halogenated ethanes versus the molar refraction (linked to polarizability) reveals a series of straight lines, each corresponding to one of nine possible arrangements of hydrogen and halogen atoms on the two-carbon skeleton. A multiple linear regression model of the boiling points could be designed based on molar refraction and subgroup structure as independent variables (R(2) = 0.995, standard error of boiling point 4.2 degrees C). The model is discussed in view of the fact that molar refraction can account for approximately 83.0% of the observed variation in boiling point, while 16.5% could be ascribed to weak C-X...H-C intermolecular interactions. The difference in the observed boiling point of molecules having similar molar refraction values but differing in hydrogen-halogen intermolecular bonds can reach as much as 90 degrees C.

Increased Patient Cost-Sharing, Weak US Economy, and Poor Health Habits: Implications for Employers and Insurers

PubMed Central

Haren, Melinda C.; McConnell, Kirk; Shinn, Arthur F.

2009-01-01

Many healthcare stakeholders, including insurers and employers, agree that growth in healthcare costs is inevitable. But the current trend toward further cost-shifting to employees and other health plan members is unsustainable. In 2008, the Zitter Group conducted a large national study on the relationship between insurers and employers, to understand how these 2 healthcare stakeholders interact in the creation of health benefit design. The survey results were previously summarized and discussed in the February/March 2009 issue of this journal. The present article aims to assess the implications of those results in the context of the growing tendency to increase patient cost-sharing, a weak US economy, and poor health habits. Increasing cost-sharing is a blunt instrument: although it may reduce utilization of frivolous services, it may also result in individuals forgoing medically necessary care. Increases in deductibles will lead to an overall decrease in optimal care-seeking behavior as families juggle healthcare costs with a weak economy and stagnating wages. PMID:25126283

Weak Lensing from Space I: Instrumentation and Survey Strategy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rhodes, Jason; Refregier, Alexandre; Massey, Richard

A wide field space-based imaging telescope is necessary to fully exploit the technique of observing dark matter via weak gravitational lensing. This first paper in a three part series outlines the survey strategies and relevant instrumental parameters for such a mission. As a concrete example of hardware design, we consider the proposed Supernova/Acceleration Probe (SNAP). Using SNAP engineering models, we quantify the major contributions to this telescope's Point Spread Function (PSF). These PSF contributions are relevant to any similar wide field space telescope. We further show that the PSF of SNAP or a similar telescope will be smaller than currentmore » ground-based PSFs, and more isotropic and stable over time than the PSF of the Hubble Space Telescope. We outline survey strategies for two different regimes - a ''wide'' 300 square degree survey and a ''deep'' 15 square degree survey that will accomplish various weak lensing goals including statistical studies and dark matter mapping.« less

STRengthening analytical thinking for observational studies: the STRATOS initiative.

PubMed

Sauerbrei, Willi; Abrahamowicz, Michal; Altman, Douglas G; le Cessie, Saskia; Carpenter, James

2014-12-30

The validity and practical utility of observational medical research depends critically on good study design, excellent data quality, appropriate statistical methods and accurate interpretation of results. Statistical methodology has seen substantial development in recent times. Unfortunately, many of these methodological developments are ignored in practice. Consequently, design and analysis of observational studies often exhibit serious weaknesses. The lack of guidance on vital practical issues discourages many applied researchers from using more sophisticated and possibly more appropriate methods when analyzing observational studies. Furthermore, many analyses are conducted by researchers with a relatively weak statistical background and limited experience in using statistical methodology and software. Consequently, even 'standard' analyses reported in the medical literature are often flawed, casting doubt on their results and conclusions. An efficient way to help researchers to keep up with recent methodological developments is to develop guidance documents that are spread to the research community at large. These observations led to the initiation of the strengthening analytical thinking for observational studies (STRATOS) initiative, a large collaboration of experts in many different areas of biostatistical research. The objective of STRATOS is to provide accessible and accurate guidance in the design and analysis of observational studies. The guidance is intended for applied statisticians and other data analysts with varying levels of statistical education, experience and interests. In this article, we introduce the STRATOS initiative and its main aims, present the need for guidance documents and outline the planned approach and progress so far. We encourage other biostatisticians to become involved. © 2014 The Authors. Statistics in Medicine published by John Wiley & Sons, Ltd.

The Importance of Longitudinal Pretest-Posttest Designs in Estimating College Impact

ERIC Educational Resources Information Center

Seifert, Tricia A.; Pascarella, Ernest T.; Erkel, Sherri I.; Goodman, Kathleen M.

2010-01-01

In this chapter, the authors discuss the issue of research design in conducting inquiry on college impact and demonstrate the importance of longitudinal pretest-posttest designs in maximizing the internal validity of findings. They begin by discussing the strengths and weaknesses of different types of research design in the college impact…

Optimally designed gold nanorattles with strong built-in hotspots and weak polarization dependence

NASA Astrophysics Data System (ADS)

Zhang, Xuemin; Wang, Tieqiang; Li, Yunong; Fu, Yu; Guo, Lei

2017-12-01

Localized electromagnetic fields generated by interparticle plasmon coupling suffer greatly from nonreproducibility because they are extremely sensitive to the nanoparticle aggregation status and the incident polarization. Here, we synthesize gold nanorattles that exhibit inherent aggregation-insensitive hotspots due to the intraparticle core-shell plasmon coupling, and investigate the structural effect on the intraparticle coupling strength and its polarization dependence. Through optimizing the structural parameters, we successfully synthesize gold nanorattles with strong built-in hotspots and weak polarization dependence. These aggregation-insensitive and weakly polarization-dependent hotspots make the Raman enhancement from nanorattle aggregates show an unusual weak dependence on the particle aggregation status, which therefore affords the opportunity to fabricate uniform and reproducible surface enhanced Raman scattering substrates.

Development of recommended resistance factors for drilled shafts in weak rocks based on o-cell tests : [technical summary].

DOT National Transportation Integrated Search

2010-03-01

Since October 1st 2007, federal-funded projects including new bridges have been mandated to be designed to meet American Association of State Highway and Transportation Officials (AASHTO) Load and Resistance Factor Design (LRFD) Bridge Design Specifi...

Investigation of allosteric modulation mechanism of metabotropic glutamate receptor 1 by molecular dynamics simulations, free energy and weak interaction analysis

NASA Astrophysics Data System (ADS)

Bai, Qifeng; Yao, Xiaojun

2016-02-01

Metabotropic glutamate receptor 1 (mGlu1), which belongs to class C G protein-coupled receptors (GPCRs), can be coupled with G protein to transfer extracellular signal by dimerization and allosteric regulation. Unraveling the dimer packing and allosteric mechanism can be of great help for understanding specific regulatory mechanism and designing more potential negative allosteric modulator (NAM). Here, we report molecular dynamics simulation studies of the modulation mechanism of FITM on the wild type, T815M and Y805A mutants of mGlu1 through weak interaction analysis and free energy calculation. The weak interaction analysis demonstrates that van der Waals (vdW) and hydrogen bonding play an important role on the dimer packing between six cholesterol molecules and mGlu1 as well as the interaction between allosteric sites T815, Y805 and FITM in wild type, T815M and Y805A mutants of mGlu1. Besides, the results of free energy calculations indicate that secondary binding pocket is mainly formed by the residues Thr748, Cys746, Lys811 and Ser735 except for FITM-bound pocket in crystal structure. Our results can not only reveal the dimer packing and allosteric regulation mechanism, but also can supply useful information for the design of potential NAM of mGlu1.

Regulatory Compliance in Multi-Tier Supplier Networks

NASA Technical Reports Server (NTRS)

Goossen, Emray R.; Buster, Duke A.

2014-01-01

Over the years, avionics systems have increased in complexity to the point where 1st tier suppliers to an aircraft OEM find it financially beneficial to outsource designs of subsystems to 2nd tier and at times to 3rd tier suppliers. Combined with challenging schedule and budgetary pressures, the environment in which safety-critical systems are being developed introduces new hurdles for regulatory agencies and industry. This new environment of both complex systems and tiered development has raised concerns in the ability of the designers to ensure safety considerations are fully addressed throughout the tier levels. This has also raised questions about the sufficiency of current regulatory guidance to ensure: proper flow down of safety awareness, avionics application understanding at the lower tiers, OEM and 1st tier oversight practices, and capabilities of lower tier suppliers. Therefore, NASA established a research project to address Regulatory Compliance in a Multi-tier Supplier Network. This research was divided into three major study efforts: 1. Describe Modern Multi-tier Avionics Development 2. Identify Current Issues in Achieving Safety and Regulatory Compliance 3. Short-term/Long-term Recommendations Toward Higher Assurance Confidence This report presents our findings of the risks, weaknesses, and our recommendations. It also includes a collection of industry-identified risks, an assessment of guideline weaknesses related to multi-tier development of complex avionics systems, and a postulation of potential modifications to guidelines to close the identified risks and weaknesses.

On Assessing the Costs and Benefits of Universal Design of ICT.

PubMed

Halbach, Till; Fuglerud, Kristin Skeide

2016-01-01

In the ICT and IT domains, Universal Design is typically viewed as a burden and an expense, and its application is often justified only by ethics and/or legislation. Advocates for Universal Design (UD) are arguing that it is cost-effective, but so far there are few studies that document this in a detailed way. In this work, we discuss related research and studies dealing with the costs and benefits of accessible and usable ICT solutions. In particular, we discuss the findings regarding what is a universally designed solution, what is needed to make such a solution, how much does it cost, what impact can be anticipated by the extra effort, and how it can be measured. Finally, we suggest an approach for carrying out cost-benefit analyses of developing universally designed solutions. There is a weak indication that the economical benefits of UD solutions are much higher than the initial and running costs.

Technologies and Designs for Electronic Nanocomputers

NASA Technical Reports Server (NTRS)

Montemerlo, Michael S.; Love, J. Christopher; Opiteck, Gregory J.; Goldhaber, David J.; Ellenbogen, James C.

1995-01-01

Diverse space-related applications have been proposed for microscopic and sub-microscopic structures, mechanisms, and 'organisms'. To govern their functions, many of these tiny systems will require even smaller, nanometer-scale programmable computers, i.e. 'nanocomputers' on-board. This paper provides an overview of the results of a nearly two-year study of the technologies and designs that presently are in development for electronic nanocomputers. Strengths and weaknesses of the various technologies and designs are discussed, as well as promising directions for remedying some of the present research issues in this area. The presentation is a synopsis of a longer MITRE review article on the same subject.

Multimodal interfaces with voice and gesture input

DOE Office of Scientific and Technical Information (OSTI.GOV)

Milota, A.D.; Blattner, M.M.

1995-07-20

The modalities of speech and gesture have different strengths and weaknesses, but combined they create synergy where each modality corrects the weaknesses of the other. We believe that a multimodal system such a one interwining speech and gesture must start from a different foundation than ones which are based solely on pen input. In order to provide a basis for the design of a speech and gesture system, we have examined the research in other disciplines such as anthropology and linguistics. The result of this investigation was a taxonomy that gave us material for the incorporation of gestures whose meaningsmore » are largely transparent to the users. This study describes the taxonomy and gives examples of applications to pen input systems.« less

Nonequilibrium Energy Transfer at Nanoscale: A Unified Theory from Weak to Strong Coupling

NASA Astrophysics Data System (ADS)

Wang, Chen; Ren, Jie; Cao, Jianshu

2015-07-01

Unraveling the microscopic mechanism of quantum energy transfer across two-level systems provides crucial insights to the optimal design and potential applications of low-dimensional nanodevices. Here, we study the non-equilibrium spin-boson model as a minimal prototype and develop a fluctuation-decoupled quantum master equation approach that is valid ranging from the weak to the strong system-bath coupling regime. The exact expression of energy flux is analytically established, which dissects the energy transfer as multiple boson processes with even and odd parity. Our analysis provides a unified interpretation of several observations, including coherence-enhanced heat flux and negative differential thermal conductance. The results will have broad implications for the fine control of energy transfer in nano-structural devices.

Systematic review of sensory integration therapy for individuals with disabilities: Single case design studies.

PubMed

Leong, H M; Carter, Mark; Stephenson, Jennifer

2015-12-01

Sensory integration therapy (SIT) is a controversial intervention that is widely used for people with disabilities. Systematic analysis was conducted on the outcomes of 17 single case design studies on sensory integration therapy for people with, or at-risk of, a developmental or learning disability, disorder or delay. An assessment of the quality of methodology of the studies found most used weak designs and poor methodology, with a tendency for higher quality studies to produce negative results. Based on limited comparative evidence, functional analysis-based interventions for challenging behavior were more effective that SIT. Overall the studies do not provide convincing evidence for the efficacy of sensory integration therapy. Given the findings of the present review and other recent analyses it is advised that the use of SIT be limited to experimental contexts. Issues with the studies and possible improvements for future research are discussed including the need to employ designs that allow for adequate demonstration of experimental control. Copyright © 2015 Elsevier Ltd. All rights reserved.

A Web-Based Monitoring System for Multidisciplinary Design Projects

NASA Technical Reports Server (NTRS)

Rogers, James L.; Salas, Andrea O.; Weston, Robert P.

1998-01-01

In today's competitive environment, both industry and government agencies are under pressure to reduce the time and cost of multidisciplinary design projects. New tools have been introduced to assist in this process by facilitating the integration of and communication among diverse disciplinary codes. One such tool, a framework for multidisciplinary computational environments, is defined as a hardware and software architecture that enables integration, execution, and communication among diverse disciplinary processes. An examination of current frameworks reveals weaknesses in various areas, such as sequencing, displaying, monitoring, and controlling the design process. The objective of this research is to explore how Web technology, integrated with an existing framework, can improve these areas of weakness. This paper describes a Web-based system that optimizes and controls the execution sequence of design processes; and monitors the project status and results. The three-stage evolution of the system with increasingly complex problems demonstrates the feasibility of this approach.

A Web-Based System for Monitoring and Controlling Multidisciplinary Design Projects

NASA Technical Reports Server (NTRS)

Salas, Andrea O.; Rogers, James L.

1997-01-01

In today's competitive environment, both industry and government agencies are under enormous pressure to reduce the time and cost of multidisciplinary design projects. A number of frameworks have been introduced to assist in this process by facilitating the integration of and communication among diverse disciplinary codes. An examination of current frameworks reveals weaknesses in various areas such as sequencing, displaying, monitoring, and controlling the design process. The objective of this research is to explore how Web technology, in conjunction with an existing framework, can improve these areas of weakness. This paper describes a system that executes a sequence of programs, monitors and controls the design process through a Web-based interface, and visualizes intermediate and final results through the use of Java(Tm) applets. A small sample problem, which includes nine processes with two analysis programs that are coupled to an optimizer, is used to demonstrate the feasibility of this approach.

Weak values of spin and momentum in atomic systems.

NASA Astrophysics Data System (ADS)

Flack, Robert; Hiley, Basil; Barker, Peter; Monachello, Vincenzo; Morley, Joel

2017-04-01

Weak values have a long history and were first considered by Landau and London in connection with superfluids. Hirschfelder called them sub-observables and Dirac anticipatied them when discussing non-commutative geometry in quantum mechanics. The idea of a weak value has returned to prominence due to Aharonov, Albert and Vaidman showing how they can be measured. They are not eigenvalues of the system and can not be measured by a collapse of the wave function with the traditional Von Neumann (strong) measurement which is a single stage process. In contrast the weak measurement process has three stages; preselection, weak stage and finally a post selection. Although weak values have been observed using photons and neutrons, we are building two experiments to observe weak values of spin and momentum in atomic systems. For spin we are following the method outlined by Duck et al which is a variant on the original Stern-Gerlach experiment using a metastable, 23S1 , form of helium. For momentum we are using a method similar to that used by Kocsis with excited argon atoms in the 3P2 state, passing through a 2-slit interferometer. The design, simulation and re John Fetzer Memorial Trust.

Design Features of Pedagogically-Sound Software in Mathematics.

ERIC Educational Resources Information Center

Haase, Howard; And Others

Weaknesses in educational software currently available in the domain of mathematics are discussed. A technique that was used for the design and production of mathematics software aimed at improving problem-solving skills which combines sound pedagogy and innovative programming is presented. To illustrate the design portion of this technique, a…

Using Design Principles to Teach Technical Communication.

ERIC Educational Resources Information Center

Markel, Mike

1995-01-01

Compares the writing of two students--a competent writer and a weak one--in a technical communication course before and after discussion of design principles. Finds that a basic understanding of design principles helped them improve document macrostructure but had little effect on document microstructure. Suggests that integrating document design…

Hybrid Computerized Adaptive Testing: From Group Sequential Design to Fully Sequential Design

ERIC Educational Resources Information Center

Wang, Shiyu; Lin, Haiyan; Chang, Hua-Hua; Douglas, Jeff

2016-01-01

Computerized adaptive testing (CAT) and multistage testing (MST) have become two of the most popular modes in large-scale computer-based sequential testing. Though most designs of CAT and MST exhibit strength and weakness in recent large-scale implementations, there is no simple answer to the question of which design is better because different…

Designing a Virtual Item Bank Based on the Techniques of Image Processing

ERIC Educational Resources Information Center

Liao, Wen-Wei; Ho, Rong-Guey

2011-01-01

One of the major weaknesses of the item exposure rates of figural items in Intelligence Quotient (IQ) tests lies in its inaccuracies. In this study, a new approach is proposed and a useful test tool known as the Virtual Item Bank (VIB) is introduced. The VIB combine Automatic Item Generation theory and image processing theory with the concepts of…

An Alternative Form of the Defense Mechanisms Inventory: Assessing Chinese University Students

ERIC Educational Resources Information Center

Zhang, Li-Fang

2016-01-01

To overcome the major weakness in the response format of the Defense Mechanisms Inventory and to use the information most relevant to the population concerned in the present study, an alternative form of the Defense Mechanisms Inventory (DMI-AF) was designed. The 80 Likert-scaled items in the inventory were tested among 385 university students in…

Improving Implementation of Function-Based Interventions: Self-Monitoring, Data Collection, and Data Review

ERIC Educational Resources Information Center

Pinkelman, Sarah E.; Horner, Robert H.

2017-01-01

The success of function-based interventions depends not just on the quality of procedures but also on the extent to which procedures are implemented as planned. Too often in schools, effort is committed to functional assessment and behavior support plan design, only to be followed by weak implementation. This study used a multiple baseline across…

Agreement and Predictive Validity Using Less Conservative FNIH Sarcopenia Project Weakness Cutpoints

PubMed Central

Shaffer, Nancy Chiles; Ferrucci, Luigi; Shardell, Michelle; Simonsick, Eleanor M.; Studenski, Stephanie

2016-01-01

OBJECTIVES The FNIH Sarcopenia Project derived conservative definitions for weakness and low lean mass, resulting in low prevalence and low agreement with prior definitions. The FNIH Project also estimated a less conservative cutpoint for low grip strength, potentially yielding a cutpoint for low lean mass more consistent with the European Working Group on Sarcopenia in Older People (EWGSOP). We derived lean mass cutpoints based on the less conservative cutpoint for grip strength (WeakI), and assessed agreement with EWGSOP and prediction of incident slow walking and mortality. DESIGN, SETTING, PARTICIPANTS, MEASUREMENTS Longitudinal analysis of 287 men and 258 women from the Baltimore Longitudinal Study of Aging aged >65 years, with 2–10 years followup. Weakness was determined via hand dynamometer, appendicular lean mass (ALM) via DEXA, and slow walking by 6m usual pace walk <0.8m/s. Analyses used classification and regression tree analysis, Cohen’s Kappa, and Cox models. RESULTS Cutpoints derived from WeakI for ALM (ALMI) and ALM adjusted for body mass index (ALM/BMII) were (ALMI) <21.4kg (men) and <14.1kg (women); and (ALM/BMII) <0.725 (men) and <0.591 (women). Kappas with EWGSOP were (ALMI); 0.65 (men) and 0.75 (women) and ALM/BMII; 0.34 (men) and 0.47 (women). In men, the hazard ratio for incident slow walking by WeakI + ALMI was 2.44 (95% CI:1.02–5.82) versus 2.91 (95% CI:1.11–7.62) by EWGSOP. Neither approach predicted incident slow walking in women. CONCLUSION The ALMI cutpoints agree with EWGSOP and predict slow walking in men. Future studies should explore sex differences in the relationship between body composition and physical function and the impact of change in muscle mass on muscle strength and physical function. PMID:28024092

Study and selection of in vivo protein interactions by coupling bimolecular fluorescence complementation and flow cytometry.

PubMed

Morell, Montse; Espargaro, Alba; Aviles, Francesc Xavier; Ventura, Salvador

2008-01-01

We present a high-throughput approach to study weak protein-protein interactions by coupling bimolecular fluorescent complementation (BiFC) to flow cytometry (FC). In BiFC, the interaction partners (bait and prey) are fused to two rationally designed fragments of a fluorescent protein, which recovers its function upon the binding of the interacting proteins. For weak protein-protein interactions, the detected fluorescence is proportional to the interaction strength, thereby allowing in vivo discrimination between closely related binders with different affinity for the bait protein. FC provides a method for high-speed multiparametric data acquisition and analysis; the assay is simple, thousands of cells can be analyzed in seconds and, if required, selected using fluorescence-activated cell sorting (FACS). The combination of both methods (BiFC-FC) provides a technically straightforward, fast and highly sensitive method to validate weak protein interactions and to screen and identify optimal ligands in biologically synthesized libraries. Once plasmids encoding the protein fusions have been obtained, the evaluation of a specific interaction, the generation of a library and selection of active partners using BiFC-FC can be accomplished in 5 weeks.

Elephants in Pyjamas: Testing the Weak Central Coherence Account of Autism Spectrum Disorders Using a Syntactic Disambiguation Task.

PubMed

Riches, N G; Loucas, T; Baird, G; Charman, T; Simonoff, E

2016-01-01

According to the weak central coherence (CC) account individuals with autism spectrum disorders (ASD) exhibit enhanced local processing and weak part-whole integration. CC was investigated in the verbal domain. Adolescents, recruited using a 2 (ASD status) by 2 (language impairment status) design, completed an aural forced choice comprehension task involving syntactically ambiguous sentences. Half the picture targets depicted the least plausible interpretation, resulting in longer RTs across groups. These were assumed to reflect local processing. There was no ASD by plausibility interaction and consequently little evidence for weak CC in the verbal domain when conceptualised as enhanced local processing. Furthermore, there was little evidence that the processing of syntactically ambiguous sentences differed as a function of ASD or language-impairment status.

Weakly supervised classification in high energy physics

DOE PAGES

Dery, Lucio Mwinmaarong; Nachman, Benjamin; Rubbo, Francesco; ...

2017-05-01

As machine learning algorithms become increasingly sophisticated to exploit subtle features of the data, they often become more dependent on simulations. Here, this paper presents a new approach called weakly supervised classification in which class proportions are the only input into the machine learning algorithm. Using one of the most challenging binary classification tasks in high energy physics $-$ quark versus gluon tagging $-$ we show that weakly supervised classification can match the performance of fully supervised algorithms. Furthermore, by design, the new algorithm is insensitive to any mis-modeling of discriminating features in the data by the simulation. Weakly supervisedmore » classification is a general procedure that can be applied to a wide variety of learning problems to boost performance and robustness when detailed simulations are not reliable or not available.« less

Weak Galerkin finite element methods for Darcy flow: Anisotropy and heterogeneity

NASA Astrophysics Data System (ADS)

Lin, Guang; Liu, Jiangguo; Mu, Lin; Ye, Xiu

2014-11-01

This paper presents a family of weak Galerkin finite element methods (WGFEMs) for Darcy flow computation. The WGFEMs are new numerical methods that rely on the novel concept of discrete weak gradients. The WGFEMs solve for pressure unknowns both in element interiors and on the mesh skeleton. The numerical velocity is then obtained from the discrete weak gradient of the numerical pressure. The new methods are quite different than many existing numerical methods in that they are locally conservative by design, the resulting discrete linear systems are symmetric and positive-definite, and there is no need for tuning problem-dependent penalty factors. We test the WGFEMs on benchmark problems to demonstrate the strong potential of these new methods in handling strong anisotropy and heterogeneity in Darcy flow.

Weakly supervised classification in high energy physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dery, Lucio Mwinmaarong; Nachman, Benjamin; Rubbo, Francesco

As machine learning algorithms become increasingly sophisticated to exploit subtle features of the data, they often become more dependent on simulations. Here, this paper presents a new approach called weakly supervised classification in which class proportions are the only input into the machine learning algorithm. Using one of the most challenging binary classification tasks in high energy physics $-$ quark versus gluon tagging $-$ we show that weakly supervised classification can match the performance of fully supervised algorithms. Furthermore, by design, the new algorithm is insensitive to any mis-modeling of discriminating features in the data by the simulation. Weakly supervisedmore » classification is a general procedure that can be applied to a wide variety of learning problems to boost performance and robustness when detailed simulations are not reliable or not available.« less

Stability of Large Parallel Tunnels Excavated in Weak Rocks: A Case Study

NASA Astrophysics Data System (ADS)

Ding, Xiuli; Weng, Yonghong; Zhang, Yuting; Xu, Tangjin; Wang, Tuanle; Rao, Zhiwen; Qi, Zufang

2017-09-01

Diversion tunnels are important structures for hydropower projects but are always placed in locations with less favorable geological conditions than those in which other structures are placed. Because diversion tunnels are usually large and closely spaced, the rock pillar between adjacent tunnels in weak rocks is affected on both sides, and conventional support measures may not be adequate to achieve the required stability. Thus, appropriate reinforcement support measures are needed, and the design philosophy regarding large parallel tunnels in weak rocks should be updated. This paper reports a recent case in which two large parallel diversion tunnels are excavated. The rock masses are thin- to ultra-thin-layered strata coated with phyllitic films, which significantly decrease the soundness and strength of the strata and weaken the rocks. The behaviors of the surrounding rock masses under original (and conventional) support measures are detailed in terms of rock mass deformation, anchor bolt stress, and the extent of the excavation disturbed zone (EDZ), as obtained from safety monitoring and field testing. In situ observed phenomena and their interpretation are also included. The sidewall deformations exhibit significant time-dependent characteristics, and large magnitudes are recorded. The stresses in the anchor bolts are small, but the extents of the EDZs are large. The stability condition under the original support measures is evaluated as poor. To enhance rock mass stability, attempts are made to reinforce support design and improve safety monitoring programs. The main feature of these attempts is the use of prestressed cables that run through the rock pillar between the parallel tunnels. The efficacy of reinforcement support measures is verified by further safety monitoring data and field test results. Numerical analysis is constantly performed during the construction process to provide a useful reference for decision making. The calculated deformations are in good agreement with the measured data, and the calculated forces of newly added cables show that the designed reinforcement is necessary and ensures sufficient stability. Finally, the role of safety monitoring in the evaluation of rock mass stability and the consideration of tunnel group effect are discussed. The work described in this paper aims to deepen the understanding of rock mass behaviors of large parallel tunnels in weak rocks and to improve the design philosophy.

Unsupervised quality estimation model for English to German translation and its application in extensive supervised evaluation.

PubMed

Han, Aaron L-F; Wong, Derek F; Chao, Lidia S; He, Liangye; Lu, Yi

2014-01-01

With the rapid development of machine translation (MT), the MT evaluation becomes very important to timely tell us whether the MT system makes any progress. The conventional MT evaluation methods tend to calculate the similarity between hypothesis translations offered by automatic translation systems and reference translations offered by professional translators. There are several weaknesses in existing evaluation metrics. Firstly, the designed incomprehensive factors result in language-bias problem, which means they perform well on some special language pairs but weak on other language pairs. Secondly, they tend to use no linguistic features or too many linguistic features, of which no usage of linguistic feature draws a lot of criticism from the linguists and too many linguistic features make the model weak in repeatability. Thirdly, the employed reference translations are very expensive and sometimes not available in the practice. In this paper, the authors propose an unsupervised MT evaluation metric using universal part-of-speech tagset without relying on reference translations. The authors also explore the performances of the designed metric on traditional supervised evaluation tasks. Both the supervised and unsupervised experiments show that the designed methods yield higher correlation scores with human judgments.

Formation Flying Design and Applications in Weak Stability Boundary Regions

NASA Technical Reports Server (NTRS)

Folta, David

2003-01-01

Weak Stability regions serve as superior locations for interferometric scientific investigations. These regions are often selected to minimize environmental disturbances and maximize observing efficiency. Design of formations in these regions are becoming ever more challenging as more complex missions are envisioned. The development of algorithms to enable the capability for formation design must be further enabled to incorporate better understanding of WSB solution space. This development will improve the efficiency and expand the capabilities of current approaches. The Goddard Space Flight Center (GSFC) is currently supporting multiple formation missions in WSB regions. This end-to-end support consists of mission operations, trajectory design, and control. It also includes both algorithm and software development. The Constellation-X, Maxim, and Stellar Imager missions are examples of the use of improved numerical methods for attaining constrained formation geometries and controlling their dynamical evolution. This paper presents a survey of formation missions in the WSB regions and a brief description of the formation design using numerical and dynamical techniques.

A Program Based on Task-Based Teaching Approach to Develop Creative Thinking Teaching Skills for Female Science Teachers in Kingdom of Saudi Arabia (KSA)

ERIC Educational Resources Information Center

Ibrahim, Manal Hassan Mohammed Bin

2015-01-01

This study aimed at developing creative thinking teaching skills for female science teachers in Kingdom of Saudi Arabia (KSA) through designing a program based on task-based teaching approach. The problem of the study was specified as the weakness of creative thinking teaching skills for science teachers in KSA and the need for programs based on…

Challenge and Opportunity: Rethinking the Role and Function of Developmental Education in Community College. CCRC Working Paper No.14

ERIC Educational Resources Information Center

Bailey, Thomas

2008-01-01

In the paper, I review evidence on the number of students who enter community colleges with weak academic skills and on the incidence of developmental education. I then report on what happens to developmental students and review the research on the effectiveness of programs at community colleges designed to strengthen weak academic skills. I…

Compensatory strategies during manual wheelchair propulsion in response to weakness in individual muscle groups: A simulation study.

PubMed

Slowik, Jonathan S; McNitt-Gray, Jill L; Requejo, Philip S; Mulroy, Sara J; Neptune, Richard R

2016-03-01

The considerable physical demand placed on the upper extremity during manual wheelchair propulsion is distributed among individual muscles. The strategy used to distribute the workload is likely influenced by the relative force-generating capacities of individual muscles, and some strategies may be associated with a higher injury risk than others. The objective of this study was to use forward dynamics simulations of manual wheelchair propulsion to identify compensatory strategies that can be used to overcome weakness in individual muscle groups and identify specific strategies that may increase injury risk. Identifying these strategies can provide rationale for the design of targeted rehabilitation programs aimed at preventing the development of pain and injury in manual wheelchair users. Muscle-actuated forward dynamics simulations of manual wheelchair propulsion were analyzed to identify compensatory strategies in response to individual muscle group weakness using individual muscle mechanical power and stress as measures of upper extremity demand. The simulation analyses found the upper extremity to be robust to weakness in any single muscle group as the remaining groups were able to compensate and restore normal propulsion mechanics. The rotator cuff muscles experienced relatively high muscle stress levels and exhibited compensatory relationships with the deltoid muscles. These results underline the importance of strengthening the rotator cuff muscles and supporting muscles whose contributions do not increase the potential for impingement (i.e., the thoracohumeral depressors) and minimize the risk of upper extremity injury in manual wheelchair users. Copyright © 2016 Elsevier Ltd. All rights reserved.

Compensatory Strategies during Manual Wheelchair Propulsion in Response to Weakness in Individual Muscle Groups: A Simulation Study

PubMed Central

Slowik, Jonathan S.; McNitt-Gray, Jill L.; Requejo, Philip S.; Mulroy, Sara J.; Neptune, Richard R.

2016-01-01

Background The considerable physical demand placed on the upper extremity during manual wheelchair propulsion is distributed among the individual muscles. The strategy used to distribute the workload is likely influenced by the relative force-generating capacities of individual muscles, and some strategies may be associated with a higher injury risk than others. The objective of this study was to use forward dynamics simulations of manual wheelchair propulsion to identify compensatory strategies that can be used to overcome weakness in individual muscle groups and identify specific strategies that may increase injury risk. Identifying these strategies can provide rationale for the design of targeted rehabilitation programs aimed at preventing the development of pain and injury in manual wheelchair users. Methods Muscle-actuated forward dynamics simulations of manual wheelchair propulsion were analyzed to identify compensatory strategies in response to individual muscle group weakness, using individual muscle mechanical power and stress as measures of upper extremity demand. Findings The simulation analyses found the upper extremity to be robust to weakness in any single muscle group as the remaining groups were able to compensate and restore normal propulsion mechanics. The rotator cuff muscles experienced relatively high muscle stress levels and exhibited compensatory relationships with the deltoid muscles. Interpretation These results underline the importance of strengthening the rotator cuff muscles and supporting muscles whose contributions do not increase the potential for impingement (i.e., the thoracohumeral depressors) and minimize the risk of upper extremity injury in manual wheelchair users. PMID:26945719

Are There Intrinsically X-Ray Quiet Quasars

NASA Technical Reports Server (NTRS)

Gallagher, S. C.; Brandt, W. N.; Laor, A.; Elvis, Martin; Mathur, S.; Wills, Beverly J.; Iyomoto, N.; White, Nicholas (Technical Monitor)

2000-01-01

Recent ROSAT studies have identified a significant population of Active Galactic Nuclei (AGN) that are notably faint in soft X-rays relative to their optical fluxes. Are these AGN intrinsically X-ray weak or are they just highly absorbed? Brandt, Laor & Wills have systematically examined the optical and UV spectral properties of a well-defined sample of these soft X-ray weak (SXW) AGN drawn from the Boroson & Green sample of all the Palomar Green AGN 00 with z < 0.5. We present ASCA observations of three of these SXW AGN: PG 1011-040, PG 1535+547 (Mrk 486), and PG 2112+059. In general, our ASCA observations support the intrinsic absorption scenario for explaining soft X-ray weakness; both PG 1535+547 and PG 2112+059 show significant column densities (NH is approximately 10(exp 22) - 10(exp 23)/sq cm) of absorbing gas. Interestingly, PG 1011-040 shows no spectral evidence for X-ray absorption. The weak X-ray emission may result from very strong absorption of a partially covered source, or this AGN may be intrinsically X-ray weak. PG 2112+059 is a Broad Absorption Line (BAL) QSO, and we find it to have the highest X-ray flux known of this class. It shows a typical power-law X-ray continuum above 3 keV; this is the first direct evidence that BAL QSOs indeed have normal X-ray continua underlying their intrinsic absorption. Finally, marked variability between the ROSAT and ASCA observations of PG 1535+547 and PG 2112+059 suggests that the soft X-ray weak designation may be transient, and multi-epoch 0.1-10.0 KeV X-ray observations are required to constrain variability of the absorber and continuum.

The relation of intrinsic religiousness to the subjective health of Greek medical inpatients: the mediating role of illness-related coping.

PubMed

Karademas, Evangelos C; Petrakis, Charoula

2009-08-01

A large number of studies suggest a significant beneficial relationship between religiousness and many health indicators. The aim of this study was to (1) examine the association between intrinsic religiousness and subjective health in a sample of medical inpatients; (2) examine the mediating role of illness-related coping. A cross-sectional design was employed. Participants were 128 inpatients suffering from a coronary artery disease, cancer, or a renal disease. Intrinsic religiousness was found to be uncorrelated to psychological symptoms or self-rated health. Weak to modest positive correlations were noticed with wishful thinking, emotional reactions, and palliative coping. These coping strategies were also found to mediate the relationship to subjective health measures. Results suggest a weak, indirect, and negative relation of intrinsic religiousness to participants' subjective health. Situational, assessment, and conceptual factors may underlie the discrepancy between these findings and research supporting the health benefits of religiousness.

Qubit absorption refrigerator at strong coupling

NASA Astrophysics Data System (ADS)

Mu, Anqi; Agarwalla, Bijay Kumar; Schaller, Gernot; Segal, Dvira

2017-12-01

We demonstrate that a quantum absorption refrigerator (QAR) can be realized from the smallest quantum system, a qubit, by coupling it in a non-additive (strong) manner to three heat baths. This function is un-attainable for the qubit model under the weak system-bath coupling limit, when the dissipation is additive. In an optimal design, the reservoirs are engineered and characterized by a single frequency component. We then obtain closed expressions for the cooling window and refrigeration efficiency, as well as bounds for the maximal cooling efficiency and the efficiency at maximal power. Our results agree with macroscopic designs and with three-level models for QARs, which are based on the weak system-bath coupling assumption. Beyond the optimal limit, we show with analytical calculations and numerical simulations that the cooling efficiency varies in a non-universal manner with model parameters. Our work demonstrates that strongly-coupled quantum machines can exhibit function that is un-attainable under the weak system-bath coupling assumption.

Design and Assessment of a Skills-Based Geoscience Curriculum

ERIC Educational Resources Information Center

Renshaw, Carl E.

2014-01-01

There is increasing interest in science curricula that engage students in scientific practices to deepen their understanding of the core ideas of the field. There are, however, few examples of their designs or assessments available for use as guides for understanding the strengths and weaknesses of particular designs. We offer a summary of our…

Process weakness assessment by profiling all incoming design components

NASA Astrophysics Data System (ADS)

Zhuang, Linda; Cai, MengFeng; Zhu, Annie; Zhang, Yifan; Sweis, Jason; Lai, Ya-Chieh

2017-03-01

Foundries normally receive a large number of designs from different customers every day. It is desired to automatically profile each incoming design to quantify certain metrics like 1) the number of polygons per GDS layers 2) what kind of electrical components the design contains 3) what the dimensions of each electrical component are 4) how frequently any size of components have been used and their physical locations. This paper will present a novel method of how to generate a complete profile of components for any particular design. The component checking flow need to be completed within hours so it will have very little impact on the tape-out time. A pre-layer checking method is also run to group commonly used layers for different electrical components and then employ different layout profiling flows. The foundry does this design chip analysis in order to find potentially weak devices due to their size or special size requirements for particular electrical components. The foundry can then take pre-emptive action to avoid yield loss or make an unnecessary mask for new incoming products before fab processing starts.

Overview of Vertical Axis Wind Turbine (VAWT)

NASA Technical Reports Server (NTRS)

Sullivan, W. N.

1979-01-01

A survey is presented of the practices which were applied for designing VAWT blades. An attempt is made to discuss strengths and weaknesses of the existing procedures. Discussion is provided on planned or suggested future work in developing improved design tools.

An optimal stratified Simon two-stage design.

PubMed

Parashar, Deepak; Bowden, Jack; Starr, Colin; Wernisch, Lorenz; Mander, Adrian

2016-07-01

In Phase II oncology trials, therapies are increasingly being evaluated for their effectiveness in specific populations of interest. Such targeted trials require designs that allow for stratification based on the participants' molecular characterisation. A targeted design proposed by Jones and Holmgren (JH) Jones CL, Holmgren E: 'An adaptive Simon two-stage design for phase 2 studies of targeted therapies', Contemporary Clinical Trials 28 (2007) 654-661.determines whether a drug only has activity in a disease sub-population or in the wider disease population. Their adaptive design uses results from a single interim analysis to decide whether to enrich the study population with a subgroup or not; it is based on two parallel Simon two-stage designs. We study the JH design in detail and extend it by providing a few alternative ways to control the familywise error rate, in the weak sense as well as the strong sense. We also introduce a novel optimal design by minimising the expected sample size. Our extended design contributes to the much needed framework for conducting Phase II trials in stratified medicine. © 2016 The Authors Pharmaceutical Statistics Published by John Wiley & Sons Ltd. © 2016 The Authors Pharmaceutical Statistics Published by John Wiley & Sons Ltd.

How Can Children with Mild Literacy Difficulties Be Supported at the Transition to Secondary School? A Small-Scale Quasi-Experimental Study

ERIC Educational Resources Information Center

Bark, Caroline; Brooks, Greg

2016-01-01

There is evidence that pupils with weak literacy skills struggle on transition to secondary school. Many experience a drop in attainment in the summer break between the two. A British government-funded programme of rigorously designed research on boosting literacy at transition had (by 2015) found only four of 15 interventions evaluated had…

Weak fault detection and health degradation monitoring using customized standard multiwavelets

NASA Astrophysics Data System (ADS)

Yuan, Jing; Wang, Yu; Peng, Yizhen; Wei, Chenjun

2017-09-01

Due to the nonobvious symptoms contaminated by a large amount of background noise, it is challenging to beforehand detect and predictively monitor the weak faults for machinery security assurance. Multiwavelets can act as adaptive non-stationary signal processing tools, potentially viable for weak fault diagnosis. However, the signal-based multiwavelets suffer from such problems as the imperfect properties missing the crucial orthogonality, the decomposition distortion impossibly reflecting the relationships between the faults and signatures, the single objective optimization and independence for fault prognostic. Thus, customized standard multiwavelets are proposed for weak fault detection and health degradation monitoring, especially the weak fault signature quantitative identification. First, the flexible standard multiwavelets are designed using the construction method derived from scalar wavelets, seizing the desired properties for accurate detection of weak faults and avoiding the distortion issue for feature quantitative identification. Second, the multi-objective optimization combined three dimensionless indicators of the normalized energy entropy, normalized singular entropy and kurtosis index is introduced to the evaluation criterions, and benefits for selecting the potential best basis functions for weak faults without the influence of the variable working condition. Third, an ensemble health indicator fused by the kurtosis index, impulse index and clearance index of the original signal along with the normalized energy entropy and normalized singular entropy by the customized standard multiwavelets is achieved using Mahalanobis distance to continuously monitor the health condition and track the performance degradation. Finally, three experimental case studies are implemented to demonstrate the feasibility and effectiveness of the proposed method. The results show that the proposed method can quantitatively identify the fault signature of a slight rub on the inner race of a locomotive bearing, effectively detect and locate the potential failure from a complicated epicyclic gear train and successfully reveal the fault development and performance degradation of a test bearing in the lifetime.

Weak Galerkin finite element methods for Darcy flow: Anisotropy and heterogeneity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Guang; Liu, Jiangguo; Mu, Lin

2014-11-01

This paper presents a family of weak Galerkin finite element methods (WGFEMs) for Darcy flow computation. The WGFEMs are new numerical methods that rely on the novel concept of discrete weak gradients. The WGFEMs solve for pressure unknowns both in element interiors and on the mesh skeleton. The numerical velocity is then obtained from the discrete weak gradient of the numerical pressure. The new methods are quite different than many existing numerical methods in that they are locally conservative by design, the resulting discrete linear systems are symmetric and positive-definite, and there is no need for tuning problem-dependent penalty factors.more » We test the WGFEMs on benchmark problems to demonstrate the strong potential of these new methods in handling strong anisotropy and heterogeneity in Darcy flow.« less

Strengths Weaknesses Opportunities and Threats of Blended Learning: Students’ Perceptions

PubMed Central

Hande, S

2014-01-01

Background: Blended learning (BL) in a cell biology course of the premedical program at the Kasturba Medical College International Centre, Manipal, India, commenced in 2006. The program provides training in basic sciences to students, especially from the United States and Canada. The approach to the study was phenomenographic, with a qualitative study design using an open-ended questionnaire, focused interviews and empirical observations. Aim: The aim of this study was to identify the strengths, weaknesses, opportunities and threats (SWOT) of BL in a premedical class. Subjects and Methods: It was a cross-sectional study. Ninety six students in a premedical cell biology class participated in the study. SWOT analysis of students’ perceptions was conducted manually. Statistical analysis included content analysis of qualitative data to classify data and aligning them into the SWOT analysis matrix. Results: The outcomes of the study revealed student perceptions in terms of SWOT of BL and the potential uses of this strategy. Conclusions: The study provides background for educators and curriculum experts to plan their modules while incorporating a BL approach. PMID:24971204

Nonequilibrium Energy Transfer at Nanoscale: A Unified Theory from Weak to Strong Coupling

PubMed Central

Wang, Chen; Ren, Jie; Cao, Jianshu

2015-01-01

Unraveling the microscopic mechanism of quantum energy transfer across two-level systems provides crucial insights to the optimal design and potential applications of low-dimensional nanodevices. Here, we study the non-equilibrium spin-boson model as a minimal prototype and develop a fluctuation-decoupled quantum master equation approach that is valid ranging from the weak to the strong system-bath coupling regime. The exact expression of energy flux is analytically established, which dissects the energy transfer as multiple boson processes with even and odd parity. Our analysis provides a unified interpretation of several observations, including coherence-enhanced heat flux and negative differential thermal conductance. The results will have broad implications for the fine control of energy transfer in nano-structural devices. PMID:26152705

A critical analysis of the numerical and analytical methods used in the construction of the lunar gravity potential model.

NASA Astrophysics Data System (ADS)

Tuckness, D. G.; Jost, B.

1995-08-01

Current knowledge of the lunar gravity field is presented. The various methods used in determining these gravity fields are investigated and analyzed. It will be shown that weaknesses exist in the current models of the lunar gravity field. The dominant part of this weakness is caused by the lack of lunar tracking data information (farside, polar areas), which makes modeling the total lunar potential difficult. Comparisons of the various lunar models reveal an agreement in the low-order coefficients of the Legendre polynomials expansions. However, substantial differences in the models can exist in the higher-order harmonics. The main purpose of this study is to assess today's lunar gravity field models for use in tomorrow's lunar mission designs and operations.

Average BER of subcarrier intensity modulated free space optical systems over the exponentiated Weibull fading channels.

PubMed

Wang, Ping; Zhang, Lu; Guo, Lixin; Huang, Feng; Shang, Tao; Wang, Ranran; Yang, Yintang

2014-08-25

The average bit error rate (BER) for binary phase-shift keying (BPSK) modulation in free-space optical (FSO) links over turbulence atmosphere modeled by the exponentiated Weibull (EW) distribution is investigated in detail. The effects of aperture averaging on the average BERs for BPSK modulation under weak-to-strong turbulence conditions are studied. The average BERs of EW distribution are compared with Lognormal (LN) and Gamma-Gamma (GG) distributions in weak and strong turbulence atmosphere, respectively. The outage probability is also obtained for different turbulence strengths and receiver aperture sizes. The analytical results deduced by the generalized Gauss-Laguerre quadrature rule are verified by the Monte Carlo simulation. This work is helpful for the design of receivers for FSO communication systems.

A Polar Corundum Oxide Displaying Weak Ferromagnetism at Room Temperature

PubMed Central

2012-01-01

Combining long-range magnetic order with polarity in the same structure is a prerequisite for the design of (magnetoelectric) multiferroic materials. There are now several demonstrated strategies to achieve this goal, but retaining magnetic order above room temperature remains a difficult target. Iron oxides in the +3 oxidation state have high magnetic ordering temperatures due to the size of the coupled moments. Here we prepare and characterize ScFeO3 (SFO), which under pressure and in strain-stabilized thin films adopts a polar variant of the corundum structure, one of the archetypal binary oxide structures. Polar corundum ScFeO3 has a weak ferromagnetic ground state below 356 K—this is in contrast to the purely antiferromagnetic ground state adopted by the well-studied ferroelectric BiFeO3. PMID:22280499

Reinforcement Learning for Weakly-Coupled MDPs and an Application to Planetary Rover Control

NASA Technical Reports Server (NTRS)

Bernstein, Daniel S.; Zilberstein, Shlomo

2003-01-01

Weakly-coupled Markov decision processes can be decomposed into subprocesses that interact only through a small set of bottleneck states. We study a hierarchical reinforcement learning algorithm designed to take advantage of this particular type of decomposability. To test our algorithm, we use a decision-making problem faced by autonomous planetary rovers. In this problem, a Mars rover must decide which activities to perform and when to traverse between science sites in order to make the best use of its limited resources. In our experiments, the hierarchical algorithm performs better than Q-learning in the early stages of learning, but unlike Q-learning it converges to a suboptimal policy. This suggests that it may be advantageous to use the hierarchical algorithm when training time is limited.

Strengths and weaknesses in the cognitive profile of youngsters with Prader-Willi syndrome.

PubMed

Curfs, L M; Wiegers, A M; Sommers, J R; Borghgraef, M; Fryns, J P

1991-12-01

In this report we present the results of a study of the intellectual functioning and cognitive profile of 26 Prader-Willi syndrome (PWS) patients. The mean IQ score was 62.3 (range 39-96). In 13 patients a significant difference between verbal and performance IQ was found. In 10 of them the performance IQ was higher than the verbal. The results of subtest analysis indicate that cognitive strengths are more visible than cognitive weaknesses. Highest scores were noted especially in the performance scale, i.e. Block Design (9 children) and Coding or Mazes (5 children). Analysis of all available data indicates that PWS patients score better on visual motor discrimination skills than on auditory verbal processing skills. These results are promising for intervention programs and education strategies.

Nursing Education Interventions for Managing Acute Pain in Hospital Settings: A Systematic Review of Clinical Outcomes and Teaching Methods.

PubMed

Drake, Gareth; de C Williams, Amanda C

2017-02-01

The objective of this review was to examine the effects of nursing education interventions on clinical outcomes for acute pain management in hospital settings, relating interventions to health care behavior change theory. Three databases were searched for nursing education interventions from 2002 to 2015 in acute hospital settings with clinical outcomes reported. Methodological quality was rated as strong, moderate, or weak using the Effective Public Health Practice Project Quality Assessment Tool for quantitative studies. The 12 eligible studies used varied didactic and interactive teaching methods. Several studies had weaknesses attributable to selection biases, uncontrolled confounders, and lack of blinding of outcome assessors. No studies made reference to behavior change theory in their design. Eight of the 12 studies investigated nursing documentation of pain assessment as the main outcome, with the majority reporting positive effects of education interventions on nursing pain assessment. Of the remaining studies, two reported mixed findings on patient self-report of pain scores as the key measure, one reported improvements in patient satisfaction with pain management after a nursing intervention, and one study found an increase in nurses' delivery of a relaxation treatment following an intervention. Improvements in design and evaluation of nursing education interventions are suggested, drawing on behavior change theory and emphasizing the relational, contextual, and emotionally demanding nature of nursing pain management in hospital settings. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

Perspective: Randomized Controlled Trials Are Not a Panacea for Diet-Related Research12

PubMed Central

Hébert, James R; Frongillo, Edward A; Adams, Swann A; Turner-McGrievy, Gabrielle M; Hurley, Thomas G; Miller, Donald R; Ockene, Ira S

2016-01-01

Research into the role of diet in health faces a number of methodologic challenges in the choice of study design, measurement methods, and analytic options. Heavier reliance on randomized controlled trial (RCT) designs is suggested as a way to solve these challenges. We present and discuss 7 inherent and practical considerations with special relevance to RCTs designed to study diet: 1) the need for narrow focus; 2) the choice of subjects and exposures; 3) blinding of the intervention; 4) perceived asymmetry of treatment in relation to need; 5) temporal relations between dietary exposures and putative outcomes; 6) strict adherence to the intervention protocol, despite potential clinical counter-indications; and 7) the need to maintain methodologic rigor, including measuring diet carefully and frequently. Alternatives, including observational studies and adaptive intervention designs, are presented and discussed. Given high noise-to-signal ratios interjected by using inaccurate assessment methods in studies with weak or inappropriate study designs (including RCTs), it is conceivable and indeed likely that effects of diet are underestimated. No matter which designs are used, studies will require continued improvement in the assessment of dietary intake. As technology continues to improve, there is potential for enhanced accuracy and reduced user burden of dietary assessments that are applicable to a wide variety of study designs, including RCTs. PMID:27184269

Coformer selection based on degradation pathway of drugs: a case study of adefovir dipivoxil-saccharin and adefovir dipivoxil-nicotinamide cocrystals.

PubMed

Gao, Yuan; Gao, Jing; Liu, Ziling; Kan, Hongliang; Zu, Hui; Sun, Wanjin; Zhang, Jianjun; Qian, Shuai

2012-11-15

Adefovir dipivoxil (AD) is a bis(pivaloyloxymethyl) prodrug of adefovir with chemical stability problem. It undergoes two degradation pathways including hydrolysis and dimerization during storage. Pharmaceutical cocrystallization exhibits a promising approach to enhance aqueous solubility as well as physicochemical stability. In this study we attempted to prepare and investigate the physiochemical properties of AD cocrystals, which were formed with two coformers having different acidity and alkalinity (weakly acidic saccharin (SAC) and weakly basic nicotinamide (NCT)). The presence of different coformer molecules along with AD resulted in altered physicochemical properties. AD-SAC cocrystal showed great improvement in solubility and chemical stability, while AD-NCT did not. Several potential factors giving rise to different solid-state properties were summarized. Different coformers resulted in different cocrystal formation, packing style and hydrogen bond formation. This study could provide the coformer selection strategy based on degradation pathways for some unstable drugs in pharmaceutical cocrystal design. Copyright © 2012 Elsevier B.V. All rights reserved.

Adapting Cognitive Walkthrough to Support Game Based Learning Design

ERIC Educational Resources Information Center

Farrell, David; Moffat, David C.

2014-01-01

For any given Game Based Learning (GBL) project to be successful, the player must learn something. Designers may base their work on pedagogical research, but actual game design is still largely driven by intuition. People are famously poor at unsupported methodical thinking and relying so much on instinct is an obvious weak point in GBL design…

Literate Specification: Using Design Rationale To Support Formal Methods in the Development of Human-Machine Interfaces.

ERIC Educational Resources Information Center

Johnson, Christopher W.

1996-01-01

The development of safety-critical systems (aircraft cockpits and reactor control rooms) is qualitatively different from that of other interactive systems. These differences impose burdens on design teams that must ensure the development of human-machine interfaces. Analyzes strengths and weaknesses of formal methods for the design of user…

Organisational design for an integrated oncological department

PubMed Central

Meiss-de Haas, Ch.L.; Falkmann, H.; Douma, J.; van Gassel, J.G.; Peters, W.G.; van Mierlo, R.; van Turnhout, J.M.; Verhagen, C.A.H.H.V.M.; Schrijvers, A.J.P.

2001-01-01

Abstract Objective The outcomes of a Strength, Weakness, Opportunities and Threat (SWOT) analysis of three Integrated Oncological Departments were compared with their present situation three years later to define factors that can influence a successful implementation and development of an Integrated Oncological Department in- and outside (i.e. home care) the hospital. Research design Comparative Qualitative Case Study. Methods Auditing based on care-as-usual norms by an external, experienced auditing committee. Research setting Integrated Oncological Departments of three hospitals. Results Successful multidisciplinary care in an integrated, oncological department needs broad support inside the hospital and a well-defined organisational plan. PMID:16896411

PACE team response shows a disregard for the principles of science.

PubMed

Edwards, Jonathan

2017-08-01

The PACE trial of cognitive behavioural therapy and graded exercise therapy for chronic fatigue syndrome/myalgic encephalomyelitis has raised serious questions about research methodology. An editorial article by Geraghty gives a fair account of the problems involved, if anything understating the case. The response by White et al. fails to address the key design flaw, of an unblinded study with subjective outcome measures, apparently demonstrating a lack of understanding of basic trial design requirements. The failure of the academic community to recognise the weakness of trials of this type suggests that a major overhaul of quality control is needed.

Special sliding door with storable handrail to support senior and handicapped persons to walk by themselves

NASA Astrophysics Data System (ADS)

Saitou, K.; Noda, N.-A.; Sano, Y.; Takase, Y.; Murai, K.; Wang, Z. F.; Li, S. Q.; Liu, X.; Tanaka, H.; Kubo, Y.

2018-06-01

In this paper, special sliding door is designed in order to support senior and handicapped persons to walk by themselves in hospitals and nursing facilities. This semiautomatic lifting equipment is utilized for the storable handrail to make sure the bad health persons are able to open the door by using a weak force. In this study, to design the equipment of the handrail, the theoretical formula of opening force is derived. Then the simulation is performed by varying geometrical conditions. The simulation results are compared with the experiment results.

Systematic Reviews of Mechanisms for Financing Family Planning: Findings, Implications, and Future Agenda.

PubMed

Lissner, Craig L; Ali, Moazzam

2016-12-01

The article describes an international collaboration that systematically reviewed the evidence on financing mechanisms for family planning/contraception, assessed the strength of and summarized the evidence, identified research gaps, and proposed a new research agenda to address the gaps. The review found that the evidence base is weak owing to the paucity of studies, diversity in findings, and variations in intervention, study design, and outcome measures. Of more than 17,000 papers reviewed only 38 met the eligibility criteria. A number of general recommendations on the directions and areas of future research can be drawn. There is a strong need for more robust study designs on the effectiveness of financial incentives in family planning. © 2016 The Population Council, Inc.

Methodology issues in implementation science.

PubMed

Newhouse, Robin; Bobay, Kathleen; Dykes, Patricia C; Stevens, Kathleen R; Titler, Marita

2013-04-01

Putting evidence into practice at the point of care delivery requires an understanding of implementation strategies that work, in what context and how. To identify methodological issues in implementation science using 4 studies as cases and make recommendations for further methods development. Four cases are presented and methodological issues identified. For each issue raised, evidence on the state of the science is described. Issues in implementation science identified include diverse conceptual frameworks, potential weaknesses in pragmatic study designs, and the paucity of standard concepts and measurement. Recommendations to advance methods in implementation include developing a core set of implementation concepts and metrics, generating standards for implementation methods including pragmatic trials, mixed methods designs, complex interventions and measurement, and endorsing reporting standards for implementation studies.

Approaches in Health Human Resource Forecasting: A Roadmap for Improvement.

PubMed

Rafiei, Sima; Mohebbifar, Rafat; Hashemi, Fariba; Ezzatabadi, Mohammad Ranjbar; Farzianpour, Fereshteh

2016-09-01

Forecasting the demand and supply of health manpower in an accurate manner makes appropriate planning possible. The aim of this paper was to review approaches and methods for health manpower forecasting and consequently propose the features that improve the effectiveness of this important process of health manpower planning. A literature review was conducted for studies published in English from 1990-2014 using Pub Med, Science Direct, Pro Quest, and Google Scholar databases. Review articles, qualitative studies, retrospective and prospective studies describing or applying various types of forecasting approaches and methods in health manpower forecasting were included in the review. The authors designed an extraction data sheet based on study questions to collect data on studies' references, designs, and types of forecasting approaches, whether discussed or applied, with their strengths and weaknesses. Forty studies were included in the review. As a result, two main categories of approaches (conceptual and analytical) for health manpower forecasting were identified. Each approach had several strengths and weaknesses. As a whole, most of them were faced with some challenges, such as being static and unable to capture dynamic variables in manpower forecasting and causal relationships. They also lacked the capacity to benefit from scenario making to assist policy makers in effective decision making. An effective forecasting approach is supposed to resolve all the deficits that exist in current approaches and meet the key features found in the literature in order to develop an open system and a dynamic and comprehensive method necessary for today complex health care systems.

The effectiveness of low-level diode laser therapy on orthodontic pain management: a systematic review and meta-analysis.

PubMed

Ren, Chong; McGrath, Colman; Yang, Yanqi

2015-09-01

To assess the effectiveness of diode low-level laser therapy (LLLT) for orthodontic pain control, a systematic and extensive electronic search for randomised controlled trials (RCTs) investigating the effects of diode LLLT on orthodontic pain prior to November 2014 was performed using the Cochrane Library (Issue 9, 2014), PubMed (1997), EMBASE (1947) and Web of Science (1956). The Cochrane tool for risk of bias evaluation was used to assess the bias risk in the chosen data. A meta-analysis was conducted using RevMan 5.3. Of the 186 results, 14 RCTs, with a total of 659 participants from 11 countries, were included. Except for three studies assessed as having a 'moderate risk of bias', the RCTs were rated as having a 'high risk of bias'. The methodological weaknesses were mainly due to 'blinding' and 'allocation concealment'. The meta-analysis showed that diode LLLT significantly reduced orthodontic pain by 39 % in comparison with placebo groups (P = 0.02). Diode LLLT was shown to significantly reduce the maximum pain intensity among parallel-design studies (P = 0.003 versus placebo groups; P = 0.000 versus control groups). However, no significant effects were shown for split-mouth-design studies (P = 0.38 versus placebo groups). It was concluded that the use of diode LLLT for orthodontic pain appears promising. However, due to methodological weaknesses, there was insufficient evidence to support or refute LLLT's effectiveness. RCTs with better designs and appropriate sample power are required to provide stronger evidence for diode LLLT's clinical applications.

A Review of Two Distance Learning Books [book review].

ERIC Educational Resources Information Center

Koszalka, Tiffany A.; Spector, J. Michael

2003-01-01

Reviews two books that are representative of the substantive books aimed at those who wish to design effective distance learning. Together these books provide a reasonably complete perspective on how to design effective distance learning. They have many strengths, and few weaknesses. (SLD)

Design and validation of a questionnaire to evaluate the usability of computerized critical care information systems.

PubMed

von Dincklage, Falk; Lichtner, Gregor; Suchodolski, Klaudiusz; Ragaller, Maximilian; Friesdorf, Wolfgang; Podtschaske, Beatrice

2017-08-01

The implementation of computerized critical care information systems (CCIS) can improve the quality of clinical care and staff satisfaction, but also holds risks of disrupting the workflow with consecutive negative impacts. The usability of CCIS is one of the key factors determining their benefits and weaknesses. However, no tailored instrument exists to measure the usability of such systems. Therefore, the aim of this study was to design and validate a questionnaire that measures the usability of CCIS. Following a mixed-method design approach, we developed a questionnaire comprising two evaluation models to assess the usability of CCIS: (1) the task-specific model rates the usability individually for several tasks which CCIS could support and which we derived by analyzing work processes in the ICU; (2) the characteristic-specific model rates the different aspects of the usability, as defined by the international standard "ergonomics of human-system interaction". We tested validity and reliability of the digital version of the questionnaire in a sample population. In the sample population of 535 participants both usability evaluation models showed a strong correlation with the overall rating of the system (multiple correlation coefficients ≥0.80) as well as a very high internal consistency (Cronbach's alpha ≥0.93). The novel questionnaire is a valid and reliable instrument to measure the usability of CCIS and can be used to study the influence of the usability on their implementation benefits and weaknesses.

Radiation Mitigation and Power Optimization Design Tools for Reconfigurable Hardware in Orbit

NASA Technical Reports Server (NTRS)

French, Matthew; Graham, Paul; Wirthlin, Michael; Wang, Li; Larchev, Gregory

2005-01-01

The Reconfigurable Hardware in Orbit (RHinO)project is focused on creating a set of design tools that facilitate and automate design techniques for reconfigurable computing in space, using SRAM-based field-programmable-gate-array (FPGA) technology. In the second year of the project, design tools that leverage an established FPGA design environment have been created to visualize and analyze an FPGA circuit for radiation weaknesses and power inefficiencies. For radiation, a single event Upset (SEU) emulator, persistence analysis tool, and a half-latch removal tool for Xilinx/Virtex-II devices have been created. Research is underway on a persistence mitigation tool and multiple bit upsets (MBU) studies. For power, synthesis level dynamic power visualization and analysis tools have been completed. Power optimization tools are under development and preliminary test results are positive.

Designing and evaluating a STEM teacher learning opportunity in the research university.

PubMed

Hardré, Patricia L; Ling, Chen; Shehab, Randa L; Herron, Jason; Nanny, Mark A; Nollert, Matthias U; Refai, Hazem; Ramseyer, Christopher; Wollega, Ebisa D

2014-04-01

This study examines the design and evaluation strategies for a year-long teacher learning and development experience, including their effectiveness, efficiency and recommendations for strategic redesign. Design characteristics include programmatic features and outcomes: cognitive, affective and motivational processes; interpersonal and social development; and performance activities. Program participants were secondary math and science teachers, partnered with engineering faculty mentors, in a research university-based education and support program. Data from multiple sources demonstrated strengths and weaknesses in design of the program's learning environment, including: face-to-face and via digital tools; on-site and distance community interactions; and strategic evaluation tools and systems. Implications are considered for the strategic design and evaluation of similar grant-funded research experiences intended to support teacher learning, development and transfer. Copyright © 2013 Elsevier Ltd. All rights reserved.

Abnormal fault-recovery characteristics of the fault-tolerant multiprocessor uncovered using a new fault-injection methodology

NASA Technical Reports Server (NTRS)

Padilla, Peter A.

1991-01-01

An investigation was made in AIRLAB of the fault handling performance of the Fault Tolerant MultiProcessor (FTMP). Fault handling errors detected during fault injection experiments were characterized. In these fault injection experiments, the FTMP disabled a working unit instead of the faulted unit once in every 500 faults, on the average. System design weaknesses allow active faults to exercise a part of the fault management software that handles Byzantine or lying faults. Byzantine faults behave such that the faulted unit points to a working unit as the source of errors. The design's problems involve: (1) the design and interface between the simplex error detection hardware and the error processing software, (2) the functional capabilities of the FTMP system bus, and (3) the communication requirements of a multiprocessor architecture. These weak areas in the FTMP's design increase the probability that, for any hardware fault, a good line replacement unit (LRU) is mistakenly disabled by the fault management software.

WEAK GALERKIN METHODS FOR SECOND ORDER ELLIPTIC INTERFACE PROBLEMS

PubMed Central

MU, LIN; WANG, JUNPING; WEI, GUOWEI; YE, XIU; ZHAO, SHAN

2013-01-01

Weak Galerkin methods refer to general finite element methods for partial differential equations (PDEs) in which differential operators are approximated by their weak forms as distributions. Such weak forms give rise to desirable flexibilities in enforcing boundary and interface conditions. A weak Galerkin finite element method (WG-FEM) is developed in this paper for solving elliptic PDEs with discontinuous coefficients and interfaces. Theoretically, it is proved that high order numerical schemes can be designed by using the WG-FEM with polynomials of high order on each element. Extensive numerical experiments have been carried to validate the WG-FEM for solving second order elliptic interface problems. High order of convergence is numerically confirmed in both L2 and L∞ norms for the piecewise linear WG-FEM. Special attention is paid to solve many interface problems, in which the solution possesses a certain singularity due to the nonsmoothness of the interface. A challenge in research is to design nearly second order numerical methods that work well for problems with low regularity in the solution. The best known numerical scheme in the literature is of order O(h) to O(h1.5) for the solution itself in L∞ norm. It is demonstrated that the WG-FEM of the lowest order, i.e., the piecewise constant WG-FEM, is capable of delivering numerical approximations that are of order O(h1.75) to O(h2) in the L∞ norm for C1 or Lipschitz continuous interfaces associated with a C1 or H2 continuous solution. PMID:24072935

Predictors of multidisciplinary treatment outcome in fibromyalgia:a systematic review.

PubMed

de Rooij, Aleid; Roorda, Leo D; Otten, René H J; van der Leeden, Marike; Dekker, Joost; Steultjens, Martijn P M

2013-03-01

To identify outcome predictors for multidisciplinary treatment in patients with chronic widespread pain (CWP) or fibromyalgia (FM). A systematic literature search in PubMed, PsycINFO, CINAHL, Cochrane Library, EMBASE and Pedro. Selection criteria included: age over 18; diagnosis CWP or FM; multidisciplinary treatment; longitudinal study design; original research report. Outcome domains: pain, physical functioning, emotional functioning, global treatment effect and 'others'. Methodological quality of the selected articles was assessed and a qualitative data synthesis was performed to identify the level of evidence. Fourteen studies (all with FM patients) fulfilled the selection criteria. Six were of high quality. Poorer outcome (pain, moderate evidence; physical functioning and quality of life, weak evidence) was predicted by depression. Similarly, poorer outcome was predicted by the disturbance and pain profile of the Minnesota Multiphasic Personality Inventory (MMPI), strong beliefs in fate and high disability (weak evidence). A better outcome was predicted by a worse baseline status, the dysfunctional and the adaptive copers profile of the Multidimensional Pain Inventory (MPI), and high levels of pain (weak evidence). Some predictors were related to specific multidisciplinary treatment (weak evidence). Inconclusive evidence was found for other demographic and clinical factors, cognitive and emotional factors, symptoms and physical functioning as predictors of outcome. It was found that a higher level of depression was a predictor of poor outcome in FM (moderate evidence). In addition, it was found that the baseline status, specific patient profiles, belief in fate, disability, and pain were predictors of the outcome of multidisciplinary treatment. Our results highlight the lack of high quality studies for evaluating predictors of the outcome of multidisciplinary treatment in FM. Further research on predictors of multidisciplinary treatment outcome is needed.

Microfluidics for High School Chemistry Students.

PubMed

Hemling, Melissa; Crooks, John A; Oliver, Piercen M; Brenner, Katie; Gilbertson, Jennifer; Lisensky, George C; Weibel, Douglas B

2014-01-14

We present a laboratory experiment that introduces high school chemistry students to microfluidics while teaching fundamental properties of acid-base chemistry. The procedure enables students to create microfluidic systems using nonspecialized equipment that is available in high school classrooms and reagents that are safe, inexpensive, and commercially available. The experiment is designed to ignite creativity and confidence about experimental design in a high school chemistry class. This experiment requires a computer program (e.g., PowerPoint), Shrinky Dink film, a readily available silicone polymer, weak acids, bases, and a colorimetric pH indicator. Over the span of five 45-min class periods, teams of students design and prepare devices in which two different pH solutions mix in a predictable way to create five different pH solutions. Initial device designs are instructive but rarely optimal. During two additional half-class periods, students have the opportunity to use their initial observations to redesign their microfluidic systems to optimize the outcome. The experiment exposes students to cutting-edge science and the design process, and solidifies introductory chemistry concepts including laminar flow, neutralization of weak acids-bases, and polymers.

Microfluidics for High School Chemistry Students

PubMed Central

Hemling, Melissa; Crooks, John A.; Oliver, Piercen M.; Brenner, Katie; Gilbertson, Jennifer; Lisensky, George C.; Weibel, Douglas B.

2014-01-01

We present a laboratory experiment that introduces high school chemistry students to microfluidics while teaching fundamental properties of acid–base chemistry. The procedure enables students to create microfluidic systems using nonspecialized equipment that is available in high school classrooms and reagents that are safe, inexpensive, and commercially available. The experiment is designed to ignite creativity and confidence about experimental design in a high school chemistry class. This experiment requires a computer program (e.g., PowerPoint), Shrinky Dink film, a readily available silicone polymer, weak acids, bases, and a colorimetric pH indicator. Over the span of five 45-min class periods, teams of students design and prepare devices in which two different pH solutions mix in a predictable way to create five different pH solutions. Initial device designs are instructive but rarely optimal. During two additional half-class periods, students have the opportunity to use their initial observations to redesign their microfluidic systems to optimize the outcome. The experiment exposes students to cutting-edge science and the design process, and solidifies introductory chemistry concepts including laminar flow, neutralization of weak acids–bases, and polymers. PMID:25584013

Weak Satiety Responsiveness Is a Reliable Trait Associated with Hedonic Risk Factors for Overeating among Women.

PubMed

Dalton, Michelle; Hollingworth, Sophie; Blundell, John; Finlayson, Graham

2015-09-04

Some individuals exhibit a weak satiety response to food and may be susceptible to overconsumption. The current study identified women showing consistently low or high satiety responses to standardised servings of food across four separate days and compared them on behavioural, psychological and physiological risk factors for overeating and future weight gain. In a crossover design, 30 female participants (age: 28.0 ± 10.6; body mass index (BMI): 23.1 ± 3.0) recorded sensations of hunger in the post-prandial period following four graded energy level breakfasts. Satiety quotients were calculated to compare individuals on satiety responsiveness across conditions. Body composition, resting metabolic rate (RMR), energy intake, food reward and craving, and eating behaviour traits were assessed under controlled laboratory conditions. A distinct low satiety phenotype (LSP) was identified with good consistency across separate study days. These individuals had a higher RMR, greater levels of disinhibition and reported feeling lower control over food cravings. Further, they consumed more energy and exhibited greater wanting for high-fat food. The inverse pattern of characteristics was observed in those exhibiting a consistently high satiety phenotype (HSP). Weak satiety responsiveness is a reliable trait identifiable using the satiety quotient. The LSP was characterised by distinct behavioural and psychological characteristics indicating a risk for overeating, compared to HSP.

Targeting cancer’s weaknesses (not its strengths): Therapeutic strategies suggested by the atavistic model

PubMed Central

Lineweaver, Charles H.; Davies, Paul C.W.; Vincent, Mark D.

2014-01-01

In the atavistic model of cancer progression, tumor cell dedifferentiation is interpreted as a reversion to phylogenetically earlier capabilities. The more recently evolved capabilities are compromised first during cancer progression. This suggests a therapeutic strategy for targeting cancer: design challenges to cancer that can only be met by the recently evolved capabilities no longer functional in cancer cells. We describe several examples of this target-the-weakness strategy. Our most detailed example involves the immune system. The absence of adaptive immunity in immunosuppressed tumor environments is an irreversible weakness of cancer that can be exploited by creating a challenge that only the presence of adaptive immunity can meet. This leaves tumor cells more vulnerable than healthy tissue to pathogenic attack. Such a target-the-weakness therapeutic strategy has broad applications, and contrasts with current therapies that target the main strength of cancer: cell proliferation. PMID:25043755

Weak Fault Feature Extraction of Rolling Bearings Based on an Improved Kurtogram.

PubMed

Chen, Xianglong; Feng, Fuzhou; Zhang, Bingzhi

2016-09-13

Kurtograms have been verified to be an efficient tool in bearing fault detection and diagnosis because of their superiority in extracting transient features. However, the short-time Fourier Transform is insufficient in time-frequency analysis and kurtosis is deficient in detecting cyclic transients. Those factors weaken the performance of the original kurtogram in extracting weak fault features. Correlated Kurtosis (CK) is then designed, as a more effective solution, in detecting cyclic transients. Redundant Second Generation Wavelet Packet Transform (RSGWPT) is deemed to be effective in capturing more detailed local time-frequency description of the signal, and restricting the frequency aliasing components of the analysis results. The authors in this manuscript, combining the CK with the RSGWPT, propose an improved kurtogram to extract weak fault features from bearing vibration signals. The analysis of simulation signals and real application cases demonstrate that the proposed method is relatively more accurate and effective in extracting weak fault features.

An experimental SMI adaptive antenna array for weak interfering signals

NASA Technical Reports Server (NTRS)

Dilsavor, R. L.; Gupta, I. J.

1989-01-01

A modified sample matrix inversion (SMI) algorithm designed to increase the suppression of weak interference is implemented on an existing experimental array system. The algorithm itself is fully described as are a number of issues concerning its implementation and evaluation, such as sample scaling, snapshot formation, weight normalization, power calculation, and system calibration. Several experiments show that the steady state performance (i.e., many snapshots are used to calculate the array weights) of the experimental system compares favorably with its theoretical performance. It is demonstrated that standard SMI does not yield adequate suppression of weak interference. Modified SMI is then used to experimentally increase this suppression by as much as 13dB.

The application of SVR model in the improvement of QbD: a case study of the extraction of podophyllotoxin.

PubMed

Zhai, Chun-Hui; Xuan, Jian-Bang; Fan, Hai-Liu; Zhao, Teng-Fei; Jiang, Jian-Lan

2018-05-03

In order to make a further optimization of process design via increasing the stability of design space, we brought in the model of Support Vector Regression (SVR). In this work, the extraction of podophyllotoxin was researched as a case study based on Quality by Design (QbD). We compared the fitting effect of SVR and the most used quadratic polynomial model (QPM) in QbD, and an analysis was made between the two design spaces obtained by SVR and QPM. As a result, the SVR stayed ahead of QPM in prediction accuracy, the stability of model and the generalization ability. The introduction of SVR into QbD made the extraction process of podophyllotoxin well designed and easier to control. The better fitting effect of SVR improved the application effect of QbD and the universal applicability of SVR, especially for non-linear, complicated and weak-regularity problems, widened the application field of QbD.

Reduction of Raman scattering and fluorescence from anvils in high pressure Raman scattering

NASA Astrophysics Data System (ADS)

Dierker, S. B.; Aronson, M. C.

2018-05-01

We describe a new design and use of a high pressure anvil cell that significantly reduces the Raman scattering and fluorescence from the anvils in high pressure Raman scattering experiments. The approach is particularly useful in Raman scattering studies of opaque, weakly scattering samples. The effectiveness of the technique is illustrated with measurements of two-magnon Raman scattering in La2CuO4.

Study of intelligent building system based on the internet of things

NASA Astrophysics Data System (ADS)

Wan, Liyong; Xu, Renbo

2017-03-01

In accordance with the problem such as isolated subsystems, weak system linkage and expansibility of the bus type buildings management system, this paper based on the modern intelligent buildings has studied some related technologies of the intelligent buildings and internet of things, and designed system architecture of the intelligent buildings based on the Internet of Things. Meanwhile, this paper has also analyzed wireless networking modes, wireless communication protocol and wireless routing protocol of the intelligent buildings based on the Internet of Things.

Design of cladding rods-assisted depressed-core few-mode fibers with improved modal spacing

NASA Astrophysics Data System (ADS)

Han, Jiawei; Zhang, Jie

2018-03-01

This paper investigates the design details of cladding rods-assisted (CRA) depressed-core (DC) few-mode fibers (FMFs) that feature more equally spaced linearly polarized (LP) modal effective indices, suitable for high-spatial-density weakly-coupled mode-division multiplexing systems. The influences of the index profile of cladding rods on LP mode-resolved effective index, bending sensitivity, and effective area Aeff, are numerically described. Based on the design considerations of LP modal Aeff-dependent spatial efficiency and LP modal bending loss-dependent robustness, the small LP21-LP02 and LP22-LP03 modal spacing limitations, encountered in state-of-the-art weakly-coupled step-index FMFs, have been substantially improved by at least 25%. In addition, the proposed CRA DC FMFs also show sufficiently large effective areas (in excess of 110 μm2) for all guided LP modes, which are expected to exhibit good nonlinear performance.

What Are the Strength of Recommendations and Methodologic Reporting in Health Economic Studies in Orthopaedic Surgery?

PubMed

Makhni, Eric C; Steinhaus, Michael E; Swart, Eric; Bozic, Kevin J

2015-10-01

Cost-effectiveness research is an increasingly used tool in evaluating treatments in orthopaedic surgery. Without high-quality primary-source data, the results of a cost-effectiveness study are either unreliable or heavily dependent on sensitivity analyses of the findings from the source studies. However, to our knowledge, the strength of recommendations provided by these studies in orthopaedics has not been studied. We asked: (1) What are the strengths of recommendations in recent orthopaedic cost-effectiveness studies? (2) What are the reasons authors cite for weak recommendations? (3) What are the methodologic reporting practices used by these studies? The titles of all articles published in six different orthopaedic journals from January 1, 2004, through April 1, 2014, were scanned for original health economics studies comparing two different types of treatment or intervention. The full texts of included studies were reviewed to determine the strength of recommendations determined subjectively by our study team, with studies providing equivocal conclusions stemming from a lack or uncertainty surrounding key primary data classified as weak and those with definitive conclusions not lacking in high-quality primary data classified as strong. The reasons underlying a weak designation were noted, and methodologic practices reported in each of the studies were examined using a validated instrument. A total of 79 articles met our prespecified inclusion criteria and were evaluated in depth. Of the articles included, 50 (63%) provided strong recommendations, whereas 29 (37%) provided weak recommendations. Of the 29 studies, clinical outcomes data were cited in 26 references as being insufficient to provide definitive conclusions, whereas cost and utility data were cited in 13 and seven articles, respectively. Methodologic reporting practices varied greatly, with mixed adherence to framing, costs, and results reporting. The framing variables included clearly defined intervention, adequate description of a comparator, study perspective clearly stated, and reported discount rate for future costs and quality-adjusted life years. Reporting costs variables included economic data collected alongside a clinical trial or another primary source and clear statement of the year of monetary units. Finally, results reporting included whether a sensitivity analysis was performed. Given that a considerable portion of orthopaedic cost-effectiveness studies provide weak recommendations and that methodologic reporting practices varied greatly among strong and weak studies, we believe that clinicians should exercise great caution when considering the conclusions of cost-effectiveness studies. Future research could assess the effect of such cost-effectiveness studies in clinical practice, and whether the strength of recommendations of a study's conclusions has any effect on practice patterns. Given the increasing use of cost-effectiveness studies in orthopaedic surgery, understanding the quality of these studies and the reasons that limit the ability of studies to provide more definitive recommendations is critical. Highlighting the heterogeneity of methodologic reporting practices will aid clinicians in interpreting the conclusions of cost-effectiveness studies and improve future research efforts.

Informal Reading Inventories: Creating Teacher-Designed Literature-Based Assessments

ERIC Educational Resources Information Center

Provost, Mary C.; Lambert, Monica A.; Babkie, Andrea M.

2010-01-01

Mandates emphasizing student achievement have increased the importance of appropriate assessment techniques for students in general and special education classrooms. Informal reading inventories (IRIs), designed by classroom teachers, have been proven to be an efficient and effective way to determine students' strengths, weaknesses, and strategies…

Differential polarization of cortical pyramidal neuron dendrites through weak extracellular fields

PubMed Central

Obermayer, Klaus

2018-01-01

The rise of transcranial current stimulation (tCS) techniques have sparked an increasing interest in the effects of weak extracellular electric fields on neural activity. These fields modulate ongoing neural activity through polarization of the neuronal membrane. While the somatic polarization has been investigated experimentally, the frequency-dependent polarization of the dendritic trees in the presence of alternating (AC) fields has received little attention yet. Using a biophysically detailed model with experimentally constrained active conductances, we analyze the subthreshold response of cortical pyramidal cells to weak AC fields, as induced during tCS. We observe a strong frequency resonance around 10-20 Hz in the apical dendrites sensitivity to polarize in response to electric fields but not in the basal dendrites nor the soma. To disentangle the relative roles of the cell morphology and active and passive membrane properties in this resonance, we perform a thorough analysis using simplified models, e.g. a passive pyramidal neuron model, simple passive cables and reconstructed cell model with simplified ion channels. We attribute the origin of the resonance in the apical dendrites to (i) a locally increased sensitivity due to the morphology and to (ii) the high density of h-type channels. Our systematic study provides an improved understanding of the subthreshold response of cortical cells to weak electric fields and, importantly, allows for an improved design of tCS stimuli. PMID:29727454

The Analysis of Weak Rock Using the Pressuremeter

NASA Astrophysics Data System (ADS)

Dafni, Jacob

The pressuremeter is a versatile in situ testing instrument capable of testing a large range of materials from very soft clay to weak rock. Due to limitations of other testing devices, the pressuremeter is one of the few instruments capable of capturing stiffness and strength properties of weak rock. However, data collected is only useful if the material tested is properly modeled and desirable material properties can be obtained. While constitutive models with various flows rules have been developed for pressuremeter analysis in soil, less research has been directed at model development for pressuremeter tests in weak rock. The result is pressuremeter data collected in rock is typically analyzed using models designed for soil. The aim of this study was to explore constitutive rock models for development into a pressuremeter framework. Three models were considered, with two of those three implemented for pressuremeter analysis. A Mohr-Coulomb model with a tensile cutoff developed by Haberfield (1987) and a Hoek-Brown model initiated by Yang et al (2011) and further developed by the author were implemented and calibrated against a data set of pressuremeter tests from 5 project test sites including a total of 115 pressuremeter tests in a number of different rock formations. Development of a multiscale damage model established by Kondo et al (2008) was explored. However, this model requires further development to be used for pressuremeter data analysis.

The effective way

NASA Astrophysics Data System (ADS)

Fruchart, Michel; Vitelli, Vincenzo

2018-03-01

A theoretical framework for the design of so-called perturbative metamaterials, based on weakly interacting unit cells, has led to the experimental demonstration of a quadrupole topological insulator.

Re-Occupancy of Breeding Territories by Ferruginous Hawks in Wyoming: Relationships to Environmental and Anthropogenic Factors

PubMed Central

Wallace, Zachary P.; Kennedy, Patricia L.; Squires, John R.; Oakleaf, Robert J.; Olson, Lucretia E.; Dugger, Katie M.

2016-01-01

Grassland and shrubland birds are declining globally due in part to anthropogenic habitat modification. Because population performance of these species is also influenced by non-anthropogenic factors, it is important to incorporate all relevant ecological drivers into demographic models. We used design-based sampling and occupancy models to test relationships of environmental factors that influence raptor demographics with re-occupancy of breeding territories by ferruginous hawks (Buteo regalis) across Wyoming, USA, 2011–2013. We also tested correlations of territory re-occupancy with oil and gas infrastructure—a leading cause of habitat modification throughout the range of this species of conservation concern. Probability of re-occupancy was not related to any covariates we investigated in 2011, had a strong negative relationship with cover of sagebrush (Artemisia spp.) in 2012, was slightly higher for territories with artificial platforms than other nest substrates in 2013, and had a positive relationship with abundance of ground squirrels (Urocitellus spp.) that was strong in 2012 and weak in 2013. Associations with roads were weak and varied by year, road-type, and scale: in 2012, re-occupancy probability had a weak positive correlation with density of roads not associated with oil and gas fields at the territory-scale; however, in 2013 re-occupancy had a very weak negative correlation with density of oil and gas field roads near nest sites (≤500 m). Although our results indicate re-occupancy of breeding territories by ferruginous hawks was compatible with densities of anthropogenic infrastructure in our study area, the lack of relationships between oil and gas well density and territory re-occupancy may have occurred because pre-treatment data were unavailable. We used probabilistic sampling at a broad spatial extent, methods to account for imperfect detection, and conducted extensive prey sampling; nonetheless, future research using before-after-control-impact designs is needed to fully assess impacts of oil and gas development on ferruginous hawks. PMID:27049324

Re-Occupancy of Breeding Territories by Ferruginous Hawks in Wyoming: Relationships to Environmental and Anthropogenic Factors

USGS Publications Warehouse

Wallace, Zachary P.; Kennedy, Patricia L.; Squires, John R.; Oakleaf, Robert J.; Olson, Lucretia E.; Dugger, Katie M.

2016-01-01

Grassland and shrubland birds are declining globally due in part to anthropogenic habitat modification. Because population performance of these species is also influenced by non-anthropogenic factors, it is important to incorporate all relevant ecological drivers into demographic models. We used design-based sampling and occupancy models to test relationships of environmental factors that influence raptor demographics with re-occupancy of breeding territories by ferruginous hawks (Buteo regalis) across Wyoming, USA, 2011–2013. We also tested correlations of territory re-occupancy with oil and gas infrastructure—a leading cause of habitat modification throughout the range of this species of conservation concern. Probability of re-occupancy was not related to any covariates we investigated in 2011, had a strong negative relationship with cover of sagebrush (Artemisia spp.) in 2012, was slightly higher for territories with artificial platforms than other nest substrates in 2013, and had a positive relationship with abundance of ground squirrels (Urocitellus spp.) that was strong in 2012 and weak in 2013. Associations with roads were weak and varied by year, road-type, and scale: in 2012, re-occupancy probability had a weak positive correlation with density of roads not associated with oil and gas fields at the territory-scale; however, in 2013 re-occupancy had a very weak negative correlation with density of oil and gas field roads near nest sites (≤500 m). Although our results indicate re-occupancy of breeding territories by ferruginous hawks was compatible with densities of anthropogenic infrastructure in our study area, the lack of relationships between oil and gas well density and territory re-occupancy may have occurred because pre-treatment data were unavailable. We used probabilistic sampling at a broad spatial extent, methods to account for imperfect detection, and conducted extensive prey sampling; nonetheless, future research using before-after-control-impact designs is needed to fully assess impacts of oil and gas development on ferruginous hawks.

Re-Occupancy of Breeding Territories by Ferruginous Hawks in Wyoming: Relationships to Environmental and Anthropogenic Factors.

PubMed

Wallace, Zachary P; Kennedy, Patricia L; Squires, John R; Oakleaf, Robert J; Olson, Lucretia E; Dugger, Katie M

2016-01-01

Grassland and shrubland birds are declining globally due in part to anthropogenic habitat modification. Because population performance of these species is also influenced by non-anthropogenic factors, it is important to incorporate all relevant ecological drivers into demographic models. We used design-based sampling and occupancy models to test relationships of environmental factors that influence raptor demographics with re-occupancy of breeding territories by ferruginous hawks (Buteo regalis) across Wyoming, USA, 2011-2013. We also tested correlations of territory re-occupancy with oil and gas infrastructure-a leading cause of habitat modification throughout the range of this species of conservation concern. Probability of re-occupancy was not related to any covariates we investigated in 2011, had a strong negative relationship with cover of sagebrush (Artemisia spp.) in 2012, was slightly higher for territories with artificial platforms than other nest substrates in 2013, and had a positive relationship with abundance of ground squirrels (Urocitellus spp.) that was strong in 2012 and weak in 2013. Associations with roads were weak and varied by year, road-type, and scale: in 2012, re-occupancy probability had a weak positive correlation with density of roads not associated with oil and gas fields at the territory-scale; however, in 2013 re-occupancy had a very weak negative correlation with density of oil and gas field roads near nest sites (≤500 m). Although our results indicate re-occupancy of breeding territories by ferruginous hawks was compatible with densities of anthropogenic infrastructure in our study area, the lack of relationships between oil and gas well density and territory re-occupancy may have occurred because pre-treatment data were unavailable. We used probabilistic sampling at a broad spatial extent, methods to account for imperfect detection, and conducted extensive prey sampling; nonetheless, future research using before-after-control-impact designs is needed to fully assess impacts of oil and gas development on ferruginous hawks.

Naturalistic Decision Making: Implications for Design

DTIC Science & Technology

1993-04-01

Cognitive Task Analysis Decision Making Design Engineer Design System Human-Computer Interface System Development 15. NUMBER OF PAGES 182 16...people use to select a course of action. The SOAR explains how stress affects the decision making of both individuals and teams. COGNITIVE TASK ANALYSIS : This...procedures for Cognitive Task Analysis , contrasting the strengths and weaknesses of each, and showing how a Cognitive Task Analysis

Invited Review Article: Development of crystal lenses for energetic photons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smither, Robert K.

2014-08-15

This paper follows the development of crystal diffraction lenses designed to focus energetic photons. It begins with the search for a solution to the astrophysics problem of how to detect weak astrophysics sources of gamma rays and x-rays. This led to the basic designs for a lens and to the understanding of basic limitations of lens design. The discussion of the development of crystal diffraction lenses is divided into two parts: lenses using crystals with mosaic structure, and lenses that use crystals with curved crystal planes. This second group divides into two sub-groups: (1) Curved crystals that are used tomore » increase the acceptance angle of the diffraction of a monochromatic beam and to increase the energy bandwidth of the diffraction. (2) Curved crystals used to focus gamma ray beams. The paper describes how these two types of crystals affect the design of the corresponding crystal lenses in different fields: astrophysics, medical imaging, detection of weak, distant, gamma-ray sources, etc. The designs of crystal lenses for these applications are given in enough detail to allow the reader to design a lens for his own application.« less

Ground Support Strategies at the Turquoise Ridge Joint Venture, Nevada

NASA Astrophysics Data System (ADS)

Sandbak, L. A.; Rai, A. R.

2013-05-01

Weak rock masses of high grade Carlin-trend gold mineralization are encountered in the Turquoise Ridge Joint Venture underground mine. The sediments consist of very weak and altered limestone, mudstone, and carbon-rich clays. The rock mass ratings are described as very poor to poor (Bieniawski in Proceedings of the symposium on exploration for rock engineering, Johannesburg, South Africa, pp. 97-106, 1976). The undercut and fill or boxes stoping mining methods are used because of the low dipping ore body geometry, complex geology, and weak rock mass. Design criteria are chosen to keep openings in weak rock as small as possible to prevent unraveling and to minimize supplementary support. Typical ground support for drifting includes the use of bolts, mesh, spiling, and shotcrete. Quality control of cemented rock fill (CRF) through sampling and aggregate sieve testing is necessary to insure high support strength. Specific support may include shotcrete arches with steel ring sets and CRF "arches" as a replacement of weak rock masses around long-term mine openings. Movement monitoring is utilized in problem areas and is needed to quantify and validate computer modeling.

Animal Study Registries: Results from a Stakeholder Analysis on Potential Strengths, Weaknesses, Facilitators, and Barriers.

PubMed

Wieschowski, Susanne; Silva, Diego S; Strech, Daniel

2016-11-01

Publication bias in animal research, its extent, its predictors, and its potential countermeasures are increasingly discussed. Recent reports and conferences highlight the potential strengths of animal study registries (ASRs) in this regard. Others have warned that prospective registration of animal studies could diminish creativity, add administrative burdens, and complicate intellectual property issues in translational research. A literature review and 21 international key-informant interviews were conducted and thematically analyzed to develop a comprehensive matrix of main- and subcategories for potential ASR-related strengths, weaknesses, facilitators, and barriers (SWFBs). We identified 130 potential SWFBs. All stakeholder groups agreed that ASRs could in various ways improve the quality and refinement of animal studies while allowing their number to be reduced, as well as supporting meta-research on animal studies. However, all stakeholder groups also highlighted the potential for theft of ideas, higher administrative burdens, and reduced creativity and serendipity in animal studies. Much more detailed reasoning was captured in the interviews than is currently found in the literature, providing a comprehensive account of the issues and arguments around ASRs. All stakeholder groups highlighted compelling potential strengths of ASRs. Although substantial weaknesses and implementation barriers were highlighted as well, different governance measures might help to minimize or even eliminate their impact. Such measures might include confidentiality time frames for accessing prospectively registered protocols, harmonized reporting requirements across ASRs, ethics reviews, lab notebooks, and journal submissions. The comprehensive information gathered in this study could help to guide a more evidence-based debate and to design pilot tests for ASRs.

Parametric Amplification For Detecting Weak Optical Signals

NASA Technical Reports Server (NTRS)

Hemmati, Hamid; Chen, Chien; Chakravarthi, Prakash

1996-01-01

Optical-communication receivers of proposed type implement high-sensitivity scheme of optical parametric amplification followed by direct detection for reception of extremely weak signals. Incorporates both optical parametric amplification and direct detection into optimized design enhancing effective signal-to-noise ratios during reception in photon-starved (photon-counting) regime. Eliminates need for complexity of heterodyne detection scheme and partly overcomes limitations imposed on older direct-detection schemes by noise generated in receivers and by limits on quantum efficiencies of photodetectors.

The technology on noise reduction of the APD detection circuit

NASA Astrophysics Data System (ADS)

Wu, Xue-ying; Zheng, Yong-chao; Cui, Jian-yong

2013-09-01

The laser pulse detection is widely used in the field of laser range finders, laser communications, laser radar, laser Identification Friend or Foe, et al, for the laser pulse detection has the advantage of high accuracy, high sensitivity and strong anti-interference. The avalanche photodiodes (APD) has the advantage of high quantum efficiency, high response speed and huge gain. The APD is particularly suitable for weak signal detection. The technology that APD acts as the photodetector for weak signal reception and amplification is widely used in laser pulse detection. The APD will convert the laser signal to weak electrical signal. The weak signal is amplified, processed and exported by the circuit. In the circuit design, the optimal signal detection is one key point in photoelectric detection system. The issue discusses how to reduce the noise of the photoelectric signal detection circuit and how to improve the signal-to-noise ratio, related analysis and practice included. The essay analyzes the mathematical model of the signal-to-noise ratio for photoelectric conversion and the noise of the APD photoelectric detection system. By analysis the bandwidth of the detection system is determined, and the circuit devices are selected that match the APD. In the circuit design separated devices with low noise are combined with integrated operational amplifier for the purpose of noise reduction. The methods can effectively suppress the noise, and improve the detection sensitivity.

Experimental Investigation of Effectiveness of Magnetic Field on Food Freezing Process

NASA Astrophysics Data System (ADS)

Suzuki, Toru; Takeuchi, Yuri; Masuda, Kazunori; Watanabe, Manabu; Shirakashi, Ryo; Fukuda, Yutaka; Tsuruta, Takaharu; Yamamoto, Kazutaka; Koga, Nobumitsu; Hiruma, Naoya; Ichioka, Jun; Takai, Kiyoshi

Recently, several food refrigeration equipments that utilize magnetic field have attracted much attention from food production companies, consumers and mass media. However, the effectiveness of the freezers is not scientifically examined. Therefore, the effectiveness should be clarified by experiments or theoretical considerations. In this study, the effect of weak magnetic field (about 0.0005 T) on freezing process of several kinds of foods was investigated by using a specially designed freezer facilitated with magnetic field generator. The investigation included the comparison of freezing curves, drip amount, physicochemical evaluations on color and texture, observation of microstructure, and sensory evaluation. From the results of the control experiments, it can be concluded that weak magnetic field around 0.0005 T provided no significant difference on temperature history during freezing and on the qualities of frozen foods, within our experimental conditions.

Optical generation of millimeter-wave pulses using a fiber Bragg grating in a fiber-optics system.

PubMed

Ye, Qing; Qu, Ronghui; Fang, Zujie

2007-04-10

A scheme is proposed to transform an optical pulse into a millimeter-wave frequency modulation pulse by using a weak fiber Bragg grating (FBG) in a fiber-optics system. The Fourier transformation method is used to obtain the required spectrum response function of the FBG for the Gaussian pulse, soliton pulse, and Lorenz shape pulse. On the condition of the first-order Born approximation of the weak fiber grating, the relation of the refractive index distribution and the spectrum response function of the FBG satisfies the Fourier transformation, and the corresponding refractive index distribution forms are obtained for single-frequency modulation and linear-frequency modulation millimeter-wave pulse generation. The performances of the designed fiber gratings are also studied by a numerical simulation method for a supershort pulse transmission.

Study on digital closed-loop system of silicon resonant micro-sensor

NASA Astrophysics Data System (ADS)

Xu, Yefeng; He, Mengke

2008-10-01

Designing a micro, high reliability weak signal extracting system is a critical problem need to be solved in the application of silicon resonant micro-sensor. The closed-loop testing system based on FPGA uses software to replace hardware circuit which dramatically decrease the system's mass and power consumption and make the system more compact, both correlation theory and frequency scanning scheme are used in extracting weak signal, the adaptive frequency scanning arithmetic ensures the system real-time. The error model was analyzed to show the solution to enhance the system's measurement precision. The experiment results show that the closed-loop testing system based on FPGA has the personality of low power consumption, high precision, high-speed, real-time etc, and also the system is suitable for different kinds of Silicon Resonant Micro-sensor.

Intercomparison Project on Parameterizations of Large-Scale Dynamics for Simulations of Tropical Convection

NASA Astrophysics Data System (ADS)

Sobel, A. H.; Wang, S.; Bellon, G.; Sessions, S. L.; Woolnough, S.

2013-12-01

Parameterizations of large-scale dynamics have been developed in the past decade for studying the interaction between tropical convection and large-scale dynamics, based on our physical understanding of the tropical atmosphere. A principal advantage of these methods is that they offer a pathway to attack the key question of what controls large-scale variations of tropical deep convection. These methods have been used with both single column models (SCMs) and cloud-resolving models (CRMs) to study the interaction of deep convection with several kinds of environmental forcings. While much has been learned from these efforts, different groups' efforts are somewhat hard to compare. Different models, different versions of the large-scale parameterization methods, and experimental designs that differ in other ways are used. It is not obvious which choices are consequential to the scientific conclusions drawn and which are not. The methods have matured to the point that there is value in an intercomparison project. In this context, the Global Atmospheric Systems Study - Weak Temperature Gradient (GASS-WTG) project was proposed at the Pan-GASS meeting in September 2012. The weak temperature gradient approximation is one method to parameterize large-scale dynamics, and is used in the project name for historical reasons and simplicity, but another method, the damped gravity wave (DGW) method, will also be used in the project. The goal of the GASS-WTG project is to develop community understanding of the parameterization methods currently in use. Their strengths, weaknesses, and functionality in models with different physics and numerics will be explored in detail, and their utility to improve our understanding of tropical weather and climate phenomena will be further evaluated. This presentation will introduce the intercomparison project, including background, goals, and overview of the proposed experimental design. Interested groups will be invited to join (it will not be too late), and preliminary results will be presented.

MEMS Based Micro Aerial Vehicles

NASA Astrophysics Data System (ADS)

Joshi, Niranjan; Köhler, Elof; Enoksson, Peter

2016-10-01

Designing a flapping wing insect robot requires understanding of insect flight mechanisms, wing kinematics and aerodynamic forces. These subsystems are interconnected and their dependence on one another affects the overall performance. Additionally it requires an artificial muscle like actuator and transmission to power the wings. Several kinds of actuators and mechanisms are candidates for this application with their own strengths and weaknesses. This article provides an overview of the insect scaled flight mechanism along with discussion of various methods to achieve the Micro Aerial Vehicle (MAV) flight. Ongoing projects in Chalmers is aimed at developing a low cost and low manufacturing time MAV. The MAV design considerations and design specifications are mentioned. The wings are manufactured using 3D printed carbon fiber and are under experimental study.

Relationship between emotional distress and quality of life on type 2 diabetes mellitus patients in Meranti island regency hospital

NASA Astrophysics Data System (ADS)

Faridah, I. N.; Perwitasari, D. A.; Pusfita, M.; Jasman, H.

2017-11-01

Type 2 Diabetes mellitus (T2DM) always got treatment for a long time so that it can affect the emotional distress and the quality of life. This study aimed to find the relationship between emotional distress with quality of life. This study used cross sectional design. DDS was used to measure patients emotional distress. EQ-5D was used to measure patients quality of life. Subjects of this study were T2DM patients ICD X.E11 with aged over 18 years old. A total of 80 patients participated in the study. The result showed that the mean of score on emotional burden was 2.985±0.678, physician distress was 2.650±0.801, regiment distress was 3.222±0.75 and interpersonal distress was 2.529±0.859. The result of the analysis showed that there was relationship between employment and interpersonal distress with index and correlation showed weak negative (r-0.212, -0.306) and significant relationship (p<0.05). The relationship between education and VAS showed weak positive correlation (r0.334) and significant relationship (p<0.01). The relationship between employment and emotional burden with VAS showed weak negative correlation (r-0.215, -0.251) and significant relationship (p<0.01). Employment and education was factors that affected the quality of life. High emotional distress can degraded the quality of life.

Computational approach for designing thermostable Candida antarctica lipase B by molecular dynamics simulation.

PubMed

Park, Hyun June; Park, Kyungmoon; Kim, Yong Hwan; Yoo, Young Je

2014-12-20

Candida antarctica lipase B (CalB) is one of the most useful enzyme for various reactions and bioconversions. Enhancing thermostability of CalB is required for industrial applications. In this study, we propose a computational design strategy to improve the thermostability of CalB. Molecular dynamics simulations at various temperatures were used to investigate the common fluctuation sites in CalB, which are considered to be thermally weak points. The RosettaDesign algorithm was used to design the selected residues. The redesigned CalB was simulated to verify both the enhancement of intramolecular interactions and the lowering of the overall root-mean-square deviation (RMSD) values. The A251E mutant designed using this strategy showed a 2.5-fold higher thermostability than the wild-type CalB. This strategy could apply to other industry applicable enzymes. Copyright © 2014 Elsevier B.V. All rights reserved.

Design principles for wave plate metasurfaces using plasmonic L-shaped nanoantennas

NASA Astrophysics Data System (ADS)

Tahir, Asad A.; Schulz, Sebastian A.; De Leon, Israel; Boyd, Robert W.

2017-03-01

Plasmonic L-shaped antennas are an important building block of metasurfaces and have been used to fabricate ultra-thin wave plates. In this work we present principles that can be used to design wave plates at a wavelength of choice and for diverse application requirements using arrays of L-shaped plasmonic antennas. We derive these design principles by studying the behavior of the vast parameter space of these antenna arrays. We show that there are two distinct regimes: a weak inter-particle coupling and a strong inter-particle coupling regime. We describe the behavior of the antenna array in each regime with regards to wave plate functionality, without resorting to approximate theoretical models. Our work is the first to explain these design principles and serves as a guide for designing wave plates for specific application requirements using plasmonic L-shaped antenna arrays.

[Analysis of the patient safety culture in hospitals of the Spanish National Health System].

PubMed

Saturno, P J; Da Silva Gama, Z A; de Oliveira-Sousa, S L; Fonseca, Y A; de Souza-Oliveira, A C; Castillo, Carmen; López, M José; Ramón, Teresa; Carrillo, Andrés; Iranzo, M Dolores; Soria, Victor; Saturno, Pedro J; Parra, Pedro; Gomis, Rafael; Gascón, Juan José; Martinez, José; Arellano, Carmen; Gama, Zenewton A Da Silva; de Oliveira-Sousa, Silvana L; de Souza-Oliveira, Adriana C; Fonseca, Yadira A; Ferreira, Marta Sobral

2008-12-01

A safety culture is essential to minimize errors and adverse events. Its measurement is needed to design activities in order to improve it. This paper describes the methods and main results of a study on safety climate in a nation-wide representative sample of public hospitals of the Spanish NHS. The Hospital Survey on Patient Safety Culture questionnaire was distributed to a random sample of health professionals in a representative sample of 24 hospitals, proportionally stratified by hospital size. Results are analyzed to provide a description of safety climate, its strengths and weaknesses. Differences by hospital size, type of health professional and service are analyzed using ANOVA. A total of 2503 responses are analyzed (response rate: 40%, (93% from professionals with direct patient contact). A total of 50% gave patient safety a score from 6 to 8 (on a 10-point scale); 95% reported < 2 events last year. Dimensions "Teamwork within hospital units" (71.8 [1.8]) and "Supervisor/Manager expectations and actions promoting safety" (61.8 [1.7]) have the highest percentage of positive answers. "Staffing", "Teamwork across hospital units", "Overall perceptions of safety" and "Hospital management support for patient safety" could be identified as weaknesses. Significant differences by hospital size, type of professional and service suggest a generally more positive attitude in small hospitals and Pharmacy services, and a more negative one in physicians. Strengths and weaknesses of the safety climate in the hospitals of the Spanish NHS have been identified and they are used to design appropriate strategies for improvement.

End User Evaluations

NASA Astrophysics Data System (ADS)

Jay, Caroline; Lunn, Darren; Michailidou, Eleni

As new technologies emerge, and Web sites become increasingly sophisticated, ensuring they remain accessible to disabled and small-screen users is a major challenge. While guidelines and automated evaluation tools are useful for informing some aspects of Web site design, numerous studies have demonstrated that they provide no guarantee that the site is genuinely accessible. The only reliable way to evaluate the accessibility of a site is to study the intended users interacting with it. This chapter outlines the processes that can be used throughout the design life cycle to ensure Web accessibility, describing their strengths and weaknesses, and discussing the practical and ethical considerations that they entail. The chapter also considers an important emerging trend in user evaluations: combining data from studies of “standard” Web use with data describing existing accessibility issues, to drive accessibility solutions forward.

Use of Electrically Evoked Compound Action Potentials for Cochlear Implant Fitting: A Systematic Review.

PubMed

de Vos, Johan J; Biesheuvel, Jan Dirk; Briaire, Jeroen J; Boot, Pieter S; van Gendt, Margriet J; Dekkers, Olaf M; Fiocco, Marta; Frijns, Johan H M

The electrically evoked compound action potential (eCAP) is widely used in the clinic as an objective measure to assess cochlear implant functionality. During the past decade, there has been increasing interest in applying eCAPs for fitting of cochlear implants. Several studies have shown that eCAP-based fitting can potentially replace time-consuming behavioral fitting procedures, especially in young children. However, a closer look to all available literature revealed that there is no clear consensus on the validity of this fitting procedure. This study evaluated the validity of eCAP-based fitting of cochlear implant recipients based on a systematic review of the recent literature. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses were used to search the PubMed, Web of Science, and Cochrane Library databases. The term "eCAP" was combined with "cochlear implants," "thresholds," and "levels," in addition to a range of related terms. Finally, 32 studies met the inclusion criteria. These studies were evaluated on the risk of bias and, when possible, compared by meta-analysis. Almost all assessed studies suffered from some form of risk of bias. Twenty-nine of the studies based their conclusion on a group correlation instead of individual subject correlations (analytical bias); 14 studies were unclear about randomization or blinding (outcome assessment bias); 9 studies provided no clear description of the populations used, for example, prelingually or postlingually implanted subjects (selection bias); and 4 studies had a high rate of loss (>10%) for patients or electrodes (attrition bias). Meta-analysis of these studies revealed a weak pooled correlation between eCAP thresholds and both behavioral T- and C-levels (r = 0.58 and r = 0.61, respectively). This review shows that the majority of the assessed studies suffered from substantial shortcomings in study design and statistical analysis. Meta-analysis showed that there is only weak evidence to support the use of eCAP data for cochlear implant fitting purposes; eCAP thresholds are an equally weak predictor for both T- and C-levels. Based on this review, it can be concluded that research on eCAP-based fitting needs a profound reflection on study design and analysis to draw well-grounded conclusions about the validity of eCAP-based fitting of cochlear implant recipients.

Alternative System Designs for Navy Undergraduate Pilot Training, Post 1975.

DTIC Science & Technology

1975-06-01

Experimental Center (NAFEC), Atlantic City, New Jersey and for the val Training Equipment Center at Marine Corps Air Station, El Toro , lifornia. The...appendix A and to the individuals too numerous to identify who provided data and ad- vice during the course of this study. Particular appreciation is...section, but no attempt has been made to compare their relative merits. Navy UPT, current and planned, was critically examined to assess strong and weak

Longwall gate road stability in a steeply pitching thick coal seam with a weak roof. Report of investigations/1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barron, L.R.; DeMarco, M.J.

1995-12-31

The U.S. Bureau of Mines conducted a ground pressure analysis of a wide abutment-type chain pillar in a two-entry gate road of a Western U.S. coal mine with an extremely weak immediate roof. This report discusses gate road layout and performance and secondary support effectiveness. The results of the pillar pressure study are compared to pillar loading predicted by a widely used pillar design method and to similar studies in other mines. A stability evaluation of the most recent longwall headgate, using the USBM Analysis of Longwall Pillar Stability (ALPS) indicates marginal stability in first-panel mining and instability in second-panelmore » mining. ALPS and the USBM Coal Mine Roof Rating (CMRR) system are used to evaluate tailgate-mining stability of the previous gate roads and to determine pillar and entry width and top coal thickness criteria for tailgate stability in future panels.« less

Detecting technology of biophotons

NASA Astrophysics Data System (ADS)

Ma, Junfu; Zhu, Zhaohui; Zhu, Yanbin

2002-03-01

A key technique of detecting the ultra-weak photon emission from biological system (UPE) is to change the light signal of an extremely weak level into electric signal of a considerable level when the photo-electric detecting system were be applied. This paper analyzed the difficult for detecting the ultra-weak photon emission from biological system (UPE) mainly is in the absence of high sensitivity detector in UV-visible-infra spectra region. An experimental setup for testing UPE in different spectral region was designed. Using the experimental setup the test data of different several spectral regions from 300 nm to 1060 nm has were tested. The test result show the UPE of living biological system exists in wide spectra region from UV- visible to infrared.

A lightweight solar array study

NASA Technical Reports Server (NTRS)

Josephs, R. H.

1977-01-01

A sample module was assembled to model a portion of a flexible extendable solar array, a type that promises to become the next generation of solar array design. The resulting study of this module is intended to provide technical support to the array designer for lightweight component selection, specifications, and tests. Selected from available lightweight components were 127-micron-thick wrap-around contacted solar cells, 34- micron-thick sputtered glass covers, and as a substrate a 13-micron-thick polyimide film clad with a copper printed circuit. Each component displayed weaknesses. The thin solar cells had excessive breakage losses. Sputtered glass cover adhesion was poor, and the covered cell was weaker than the cell uncovered. Thermal stresses caused some cell delamination from the model solar array substrate.

Monitoring is not enough: on the need for a model-based approach to migratory bird management

USGS Publications Warehouse

Nichols, J.D.; Bonney, Rick; Pashley, David N.; Cooper, Robert; Niles, Larry

2000-01-01

Informed management requires information about system state and about effects of potential management actions on system state. Population monitoring can provide the needed information about system state, as well as information that can be used to investigate effects of management actions. Three methods for investigating effects of management on bird populations are (1) retrospective analysis, (2) formal experimentation and constrained-design studies, and (3) adaptive management. Retrospective analyses provide weak inferences, regardless of the quality of the monitoring data. The active use of monitoring data in experimental or constrained-design studies or in adaptive management is recommended. Under both approaches, learning occurs via the comparison of estimates from the monitoring program with predictions from competing management models.

Modeling Post-Accident Vehicle Egress

DTIC Science & Technology

2013-01-01

interest for military situations may involve rolled-over vehicles for which detailed movement data are not available. In the current design process...test trials. These evaluations are expensive and time-consuming, and are often performed late in the design process when it is too difficult to...alter the design if weaknesses are discovered. Yet, due to the limitations of current software tools, digital human models (DHMs) are not yet widely

Mixed-Methods Design in Biology Education Research: Approach and Uses

PubMed Central

Warfa, Abdi-Rizak M.

2016-01-01

Educational research often requires mixing different research methodologies to strengthen findings, better contextualize or explain results, or minimize the weaknesses of a single method. This article provides practical guidelines on how to conduct such research in biology education, with a focus on mixed-methods research (MMR) that uses both quantitative and qualitative inquiries. Specifically, the paper provides an overview of mixed-methods design typologies most relevant in biology education research. It also discusses common methodological issues that may arise in mixed-methods studies and ways to address them. The paper concludes with recommendations on how to report and write about MMR. PMID:27856556

VLBI phase-referencing for observations of weak radio sources

NASA Technical Reports Server (NTRS)

Lestrade, J.-F.

1991-01-01

Phase-referencing is a technique used in VLBI to extend the signal coherence time from a few minutes to a few hours in order to enhance significantly its sensitivity. With this technique, VLBI observations of milliJansky radio sources can be conducted for high-accuracy differential astrometry as well as imaging. We describe the technique in some details and present, as an example, a submilliarcsecond differential astrometric experiment design to identify the star responsible for the weak radio emission in the binary system Algol.

Bayes factor design analysis: Planning for compelling evidence.

PubMed

Schönbrodt, Felix D; Wagenmakers, Eric-Jan

2018-02-01

A sizeable literature exists on the use of frequentist power analysis in the null-hypothesis significance testing (NHST) paradigm to facilitate the design of informative experiments. In contrast, there is almost no literature that discusses the design of experiments when Bayes factors (BFs) are used as a measure of evidence. Here we explore Bayes Factor Design Analysis (BFDA) as a useful tool to design studies for maximum efficiency and informativeness. We elaborate on three possible BF designs, (a) a fixed-n design, (b) an open-ended Sequential Bayes Factor (SBF) design, where researchers can test after each participant and can stop data collection whenever there is strong evidence for either [Formula: see text] or [Formula: see text], and (c) a modified SBF design that defines a maximal sample size where data collection is stopped regardless of the current state of evidence. We demonstrate how the properties of each design (i.e., expected strength of evidence, expected sample size, expected probability of misleading evidence, expected probability of weak evidence) can be evaluated using Monte Carlo simulations and equip researchers with the necessary information to compute their own Bayesian design analyses.

Comparison of weighting techniques for acoustic full waveform inversion

NASA Astrophysics Data System (ADS)

Jeong, Gangwon; Hwang, Jongha; Min, Dong-Joo

2017-12-01

To reconstruct long-wavelength structures in full waveform inversion (FWI), the wavefield-damping and weighting techniques have been used to synthesize and emphasize low-frequency data components in frequency-domain FWI. However, these methods have some weak points. The application of wavefield-damping method on filtered data fails to synthesize reliable low-frequency data; the optimization formula obtained introducing the weighting technique is not theoretically complete, because it is not directly derived from the objective function. In this study, we address these weak points and present how to overcome them. We demonstrate that the source estimation in FWI using damped wavefields fails when the data used in the FWI process does not satisfy the causality condition. This phenomenon occurs when a non-causal filter is applied to data. We overcome this limitation by designing a causal filter. Also we modify the conventional weighting technique so that its optimization formula is directly derived from the objective function, retaining its original characteristic of emphasizing the low-frequency data components. Numerical results show that the newly designed causal filter enables to recover long-wavelength structures using low-frequency data components synthesized by damping wavefields in frequency-domain FWI, and the proposed weighting technique enhances the inversion results.

GaAs Coupled Micro Resonators with Enhanced Sensitive Mass Detection

PubMed Central

Chopard, Tony; Lacour, Vivien; Leblois, Therese

2014-01-01

This work demonstrates the improvement of mass detection sensitivity and time response using a simple sensor structure. Indeed, complicated technological processes leading to very brittle sensing structures are often required to reach high sensitivity when we want to detect specific molecules in biological fields. These developments constitute an obstacle to the early diagnosis of diseases. An alternative is the design of coupled structures. In this study, the device is based on the piezoelectric excitation and detection of two GaAs microstructures vibrating in antisymmetric modes. GaAs is a crystal which has the advantage to be micromachined easily using typical clean room processes. Moreover, we showed its high potential in direct biofunctionalisation for use in the biological field. A specific design of the device was performed to improve the detection at low mass and an original detection method has been developed. The principle is to exploit the variation in amplitude at the initial resonance frequency which has in the vicinity of weak added mass the greatest slope. Therefore, we get a very good resolution for an infinitely weak mass: relative voltage variation of 8%/1 fg. The analysis is based on results obtained by finite element simulation. PMID:25474375

Mechanical and biomechanical analysis of a linear piston design for angular-velocity-based orthotic control.

PubMed

Lemaire, Edward D; Samadi, Reza; Goudreau, Louis; Kofman, Jonathan

2013-01-01

A linear piston hydraulic angular-velocity-based control knee joint was designed for people with knee-extensor weakness to engage knee-flexion resistance when knee-flexion angular velocity reaches a preset threshold, such as during a stumble, but to otherwise allow free knee motion. During mechanical testing at the lowest angular-velocity threshold, the device engaged within 2 degrees knee flexion and resisted moment loads of over 150 Nm. The device completed 400,000 loading cycles without mechanical failure or wear that would affect function. Gait patterns of nondisabled participants were similar to normal at walking speeds that produced below-threshold knee angular velocities. Fast walking speeds, employed purposely to attain the angular-velocity threshold and cause knee-flexion resistance, reduced maximum knee flexion by approximately 25 degrees but did not lead to unsafe gait patterns in foot ground clearance during swing. In knee collapse tests, the device successfully engaged knee-flexion resistance and stopped knee flexion with peak knee moments of up to 235.6 Nm. The outcomes from this study support the potential for the linear piston hydraulic knee joint in knee and knee-ankle-foot orthoses for people with lower-limb weakness.

School-based peer-related social competence interventions for children with autism spectrum disorder: a meta-analysis and descriptive review of single case research design studies.

PubMed

Whalon, Kelly J; Conroy, Maureen A; Martinez, Jose R; Werch, Brittany L

2015-06-01

The purpose of this review was to critically examine and summarize the impact of school-based interventions designed to facilitate the peer-related social competence of children with autism spectrum disorder (ASD). Reviewed studies employed a single-case experimental design, targeted peer-related social competence, included children 3-12 years old with an ASD, and took place in school settings. Articles were analyzed descriptively and using the evaluative method to determine study quality. Additionally, effect size estimates were calculated using nonoverlap of all pairs method and Tau-U. A total of 37 studies including 105 children were reviewed. Overall, ES estimates ranged from weak to strong, but on average, the reviewed interventions produced a moderate to strong effect, and quality ratings were generally in the acceptable to high range. Findings suggest that children with ASD can benefit from social skill interventions implemented with peers in school settings.

Evaluation and treatment of students with difficulties passing the Step examinations.

PubMed

Laatsch, Linda

2009-05-01

The author designed this retrospective case series study both to systematically examine characteristics of individuals referred for treatment after multiple failures on the United States Medical Licensing Examinations (USMLE) Step 1 or 2 administered by the National Board of Medical Examiners and to evaluate treatment effectiveness in a uniform sample. Six medical students referred to rehabilitation psychology met selection criteria. All students completed the requisite neuropsychological, academic, and psychological testing to identify cognitive and emotional strengths and weaknesses. All six underwent individualized cognitive rehabilitation (CR) with a primary focus on reading fluency and accuracy. All participants improved on a quantitative measure of reading speed and accuracy, and five of the six passed their next USLME Step examination in spite of past failures. Medical students with identified difficulties on reading fluency, but no history of a learning disability, may benefit from systematic CR that addresses cognitive weaknesses related to test-taking abilities. The strong relationships between language and reading skills and the USMLE Step examinations suggest that some students may fail these examinations because of a relative weakness in language processing and reading fluency that may prohibit their successful completion of the Step examinations.

Weak-signal Phase Calibration Strategies for Large DSN Arrays

NASA Technical Reports Server (NTRS)

Jones, Dayton L.

2005-01-01

The NASA Deep Space Network (DSN) is studying arrays of large numbers of small, mass-produced radio antennas as a cost-effective way to increase downlink sensitivity and data rates for future missions. An important issue for the operation of large arrays is the accuracy with which signals from hundreds of small antennas can be combined. This is particularly true at Ka band (32 GHz) where atmospheric phase variations can be large and rapidly changing. A number of algorithms exist to correct the phases of signals from individual antennas in the case where a spacecraft signal provides a useful signal-to-noise ratio (SNR) on time scales shorter than the atmospheric coherence time. However, for very weak spacecraft signals it will be necessary to rely on background natural radio sources to maintain array phasing. Very weak signals could result from a spacecraft emergency or by design, such as direct-to-Earth data transmissions from distant planetary atmospheric or surface probes using only low gain antennas. This paper considers the parameter space where external real-time phase calibration will be necessary, and what this requires in terms of array configuration and signal processing. The inherent limitations of this technique are also discussed.

Analysis of problem solving on project based learning with resource based learning approach computer-aided program

NASA Astrophysics Data System (ADS)

Kuncoro, K. S.; Junaedi, I.; Dwijanto

2018-03-01

This study aimed to reveal the effectiveness of Project Based Learning with Resource Based Learning approach computer-aided program and analyzed problem-solving abilities in terms of problem-solving steps based on Polya stages. The research method used was mixed method with sequential explanatory design. The subject of this research was the students of math semester 4. The results showed that the S-TPS (Strong Top Problem Solving) and W-TPS (Weak Top Problem Solving) had good problem-solving abilities in each problem-solving indicator. The problem-solving ability of S-MPS (Strong Middle Problem Solving) and (Weak Middle Problem Solving) in each indicator was good. The subject of S-BPS (Strong Bottom Problem Solving) had a difficulty in solving the problem with computer program, less precise in writing the final conclusion and could not reflect the problem-solving process using Polya’s step. While the Subject of W-BPS (Weak Bottom Problem Solving) had not been able to meet almost all the indicators of problem-solving. The subject of W-BPS could not precisely made the initial table of completion so that the completion phase with Polya’s step was constrained.

Design and Implementation of the National Seismic Monitoring Network in the Kingdom of Bhutan

NASA Astrophysics Data System (ADS)

Ohmi, S.; Inoue, H.; Chophel, J.; Pelgay, P.; Drukpa, D.

2017-12-01

Bhutan-Himalayan district is located along the plate collision zone between Indian and Eurasian plates, which is one of the most seismically active region in the world. Recent earthquakes such as M7.8 Gorkha Nepal earthquake in April 25, 2015 and M6.7 Imphal, India earthquake in January 3, 2016 are examples of felt earthquakes in Bhutan. However, there is no permanent seismic monitoring system ever established in Bhutan, whose territory is in the center of the Bhutan-Himalayan region. We started establishing permanent seismic monitoring network of minimum requirements and intensity meter network over the nation. The former is composed of six (6) observation stations in Bhutan with short period weak motion and strong motion seismometers as well as three (3) broad-band seismometers, and the latter is composed of twenty intensity meters located in every provincial government office. Obtained data are transmitted to the central processing system in the DGM office in Thimphu in real time. In this project, DGM will construct seismic vault with their own budget which is approved as the World Bank project, and Japan team assists the DGM for site survey of observation site, designing the observation vault, and designing the data telemetry system as well as providing instruments for the observation such as seismometers and digitizers. We already started the operation of the six (6) weak motion stations as well as twenty (20) intensity meter stations. Additionally, the RIMES (Regional Integrated Multi-hazard Early Warning System for Africa and Asia) is also providing eight (8) weak motion stations and we are keeping close communication to operate them as one single seismic monitoring network composed of fourteen (14) stations. This network will be definitely utilized for not only for seismic disaster mitigation of the country but also for studying the seismotectonics in the Bhutan-Himalayan region which is not yet precisely revealed due to the lack of observation data in the past.

An adaptive randomized trial of dialectical behavior therapy and cognitive behavior therapy for binge-eating.

PubMed

Chen, E Y; Cacioppo, J; Fettich, K; Gallop, R; McCloskey, M S; Olino, T; Zeffiro, T A

2017-03-01

Early weak treatment response is one of the few trans-diagnostic, treatment-agnostic predictors of poor outcome following a full treatment course. We sought to improve the outcome of clients with weak initial response to guided self-help cognitive behavior therapy (GSH). One hundred and nine women with binge-eating disorder (BED) or bulimia nervosa (BN) (DSM-IV-TR) received 4 weeks of GSH. Based on their response, they were grouped into: (1) early strong responders who continued GSH (cGSH), and early weak responders randomized to (2) dialectical behavior therapy (DBT), or (3) individual and additional group cognitive behavior therapy (CBT+). Baseline objective binge-eating-day (OBD) frequency was similar between DBT, CBT+ and cGSH. During treatment, OBD frequency reduction was significantly slower in DBT and CBT+ relative to cGSH. Relative to cGSH, OBD frequency was significantly greater at the end of DBT (d = 0.27) and CBT+ (d = 0.31) although these effects were small and within-treatment effects from baseline were large (d = 1.41, 0.95, 1.11, respectively). OBD improvements significantly diminished in all groups during 12 months follow-up but were significantly better sustained in DBT relative to cGSH (d = -0.43). At 6- and 12-month follow-up assessments, DBT, CBT and cGSH did not differ in OBD. Early weak response to GSH may be overcome by additional intensive treatment. Evidence was insufficient to support superiority of either DBT or CBT+ for early weak responders relative to early strong responders in cGSH; both were helpful. Future studies using adaptive designs are needed to assess the use of early response to efficiently deliver care to large heterogeneous client groups.

Weak Central Coherence and Its Relations to Theory of Mind and Anxiety in Autism

ERIC Educational Resources Information Center

Burnette, Courtney P.; Mundy, Peter C.; Meyer, Jessica A.; Sutton, Steven K.; Vaughan, Amy E.; Charak, David

2005-01-01

Recent theory and research suggests that weak central coherence, a specific perceptual-cognitive style, underlies the central disturbance in autism. This study sought to provide a test of the weak central coherence hypothesis. In addition, this study explored the relations between the weak central coherence hypothesis, theory of mind skills, and…

Why less may be more: a mixed methods study of the work and relatedness of ‘weak ties’ in supporting long-term condition self-management

PubMed Central

2014-01-01

Background The distribution of the roles and responsibilities of long-term condition management (LTCM) outside of formal health services implicates a wide set of relationships and activities of involvement. Yet, compared to studies of professional implementation, patient systems of implementation remain under-investigated. The aim of this paper is to explore the work, meaning and function attributed to ‘weaker’ ties relative to other more bonding relationships in order to identify the place of these within a context of systems of support for long-term conditions. Methods This is a mixed methods survey with nested qualitative study. A total of 300 people from deprived areas in the North West of England with chronic illnesses took part in a survey conducted in 2010 to 2011. A concentric circles diagram was used as a research tool with which participants identified 2,544 network members who contributed to illness management. Notions of ‘work’ were used to describe activities associated with chronic illness and to identify how weaker ties are included and perceived to be involved through social network members (SNM) contributions. Results The results provide an articulation of how SNMs are substantially involved in weak tie illness management. Weaker ties constituted 16.1% of network membership involved in illness work. The amount of work undertaken was similar but less than that of stronger ties. Weaker ties appeared more durable and less liable to loss over time than stronger ties. The qualitative accounts suggested that weak ties enabled the moral positioning of the self-managing ‘self’ and acted on the basis of a strong sense of reciprocity. Conclusions Weak ties act as an acceptable bridge between a sense of personal agency and control and the need for external support because it is possible to construct a sense of moral acceptability through reciprocal exchange. Access to weak tie resources needs to be taken into account when considering the ways in which systems of health implementation for chronic illness are designed and delivered. PMID:24524253

IDR: A Participatory Methodology for Interdisciplinary Design in Technology Enhanced Learning

ERIC Educational Resources Information Center

Winters, Niall; Mor, Yishay

2008-01-01

One of the important themes that emerged from the CAL'07 conference was the failure of technology to bring about the expected disruptive effect to learning and teaching. We identify one of the causes as an inherent weakness in prevalent development methodologies. While the problem of designing technology for learning is irreducibly…

Designing learning environments to promote student learning: ergonomics in all but name.

PubMed

Smith, Thomas J

2013-01-01

This report introduces evidence for the conclusion that a common theme underlies almost all proposed solutions for improving the performance of K-12 students, namely their reliance on the design of educational system environments, features and operations. Two categories of design factors impacting such performance are addressed: (1) 9 factors reliably shown to have a strong influence - namely environmental design of classroom and building facilities, longer exposure to learning, cooperative learning designs, early childhood education, teaching quality, nutritional adequacy, participation in physical activity, good physical fitness, and school-community integration; and (2) 11 factors with an equivocal, varied or weak influence - classroom technology, online learning environments, smaller class size, school choice, school funding, school size, school start times, teacher training level, amount of homework, student self-confidence and informal learning. It is concluded that: (1) student learning outcomes, and more broadly the edifice of education itself, are largely defined in terms of an extensive system of design factors and conditions; (2) the time is long overdue for the educational system to acknowledge the central role of E/HF design as the major influence on student performance and learning; and (3) K-12 educators and administrators should emphasize allocation of resources to design factors reliably shown to have a strongly positive impact on student performance, but should treat expenditure on factors with equivocal, varied or weak influence on such performance with more caution and/or skepticism.

Preventing unintentional injuries to children under 15 years in the outdoors: a systematic review of the effectiveness of educational programs

PubMed Central

Hunt, Harriet; Garside, Ruth; Moxham, Tiffany; Peters, Jaime; Anderson, Rob

2011-01-01

Introduction Unintentional injuries to children in the outdoors have a significant impact on child mortality, development and healthcare costs. This paper presents the findings of a systematic review about the effectiveness of programs that provided information, advice or education about the prevention of unintentional injuries to children under 15 years during outdoor play and leisure. Methods A structured search strategy was conducted in a range of databases. All report titles and abstracts were screened using pre-defined criteria. Included reports were quality appraised using a modified Graphical Appraisal Tool for Epidemiological studies (GATE) tool. All quality appraisals and data extraction were checked by a second reviewer. If not provided in the original reports, ORs and mean differences were calculated, where sufficient data were available. Results Twenty-three studies met the inclusion criteria. There was a paucity of robust study designs. The majority of studies only reported a short-term follow-up of intermediate outcome measures. Only two studies measured injury rates; both reported a reduction, but both studies also had considerable methodological weaknesses. The five studies that measured the use of protective equipment reported mixed results, although there is some evidence that suggests that more extensive educational programs (such as health fairs and media campaigns) increase their use. The 20 studies that measured behaviour, attitude or knowledge outcomes reported highly mixed results. Discussion Methodological weaknesses of the included studies limit support for a particular course of action. To better inform policy and practice, future research should (1) use robust study designs and (2) not rely on short-term proxy outcome measures. PMID:21890579

Transcranial direct current stimulation (tDCS) Paired with massed practice training to promote adaptive plasticity and motor recovery in chronic incomplete tetraplegia: a pilot study.

PubMed

Potter-Baker, Kelsey A; Janini, Daniel P; Lin, Yin-Liang; Sankarasubramanian, Vishwanath; Cunningham, David A; Varnerin, Nicole M; Chabra, Patrick; Kilgore, Kevin L; Richmond, Mary Ann; Frost, Frederick S; Plow, Ela B

2017-08-07

Objective Our goal was to determine if pairing transcranial direct current stimulation (tDCS) with rehabilitation for two weeks could augment adaptive plasticity offered by these residual pathways to elicit longer-lasting improvements in motor function in incomplete spinal cord injury (iSCI). Design Longitudinal, randomized, controlled, double-blinded cohort study. Setting Cleveland Clinic Foundation, Cleveland, Ohio, USA. Participants Eight male subjects with chronic incomplete motor tetraplegia. Interventions Massed practice (MP) training with or without tDCS for 2 hrs, 5 times a week. Outcome Measures We assessed neurophysiologic and functional outcomes before, after and three months following intervention. Neurophysiologic measures were collected with transcranial magnetic stimulation (TMS). TMS measures included excitability, representational volume, area and distribution of a weaker and stronger muscle motor map. Functional assessments included a manual muscle test (MMT), upper extremity motor score (UEMS), action research arm test (ARAT) and nine hole peg test (NHPT). Results We observed that subjects receiving training paired with tDCS had more increased strength of weak proximal (15% vs 10%), wrist (22% vs 10%) and hand (39% vs. 16%) muscles immediately and three months after intervention compared to the sham group. Our observed changes in muscle strength were related to decreases in strong muscle map volume (r=0.851), reduced weak muscle excitability (r=0.808), a more focused weak muscle motor map (r=0.675) and movement of weak muscle motor map (r=0.935). Conclusion Overall, our results encourage the establishment of larger clinical trials to confirm the potential benefit of pairing tDCS with training to improve the effectiveness of rehabilitation interventions for individuals with SCI. Trial Registration NCT01539109.

Results of the eruptive column model inter-comparison study

USGS Publications Warehouse

Costa, Antonio; Suzuki, Yujiro; Cerminara, M.; Devenish, Ben J.; Esposti Ongaro, T.; Herzog, Michael; Van Eaton, Alexa; Denby, L.C.; Bursik, Marcus; de' Michieli Vitturi, Mattia; Engwell, S.; Neri, Augusto; Barsotti, Sara; Folch, Arnau; Macedonio, Giovanni; Girault, F.; Carazzo, G.; Tait, S.; Kaminski, E.; Mastin, Larry G.; Woodhouse, Mark J.; Phillips, Jeremy C.; Hogg, Andrew J.; Degruyter, Wim; Bonadonna, Costanza

2016-01-01

This study compares and evaluates one-dimensional (1D) and three-dimensional (3D) numerical models of volcanic eruption columns in a set of different inter-comparison exercises. The exercises were designed as a blind test in which a set of common input parameters was given for two reference eruptions, representing a strong and a weak eruption column under different meteorological conditions. Comparing the results of the different models allows us to evaluate their capabilities and target areas for future improvement. Despite their different formulations, the 1D and 3D models provide reasonably consistent predictions of some of the key global descriptors of the volcanic plumes. Variability in plume height, estimated from the standard deviation of model predictions, is within ~ 20% for the weak plume and ~ 10% for the strong plume. Predictions of neutral buoyancy level are also in reasonably good agreement among the different models, with a standard deviation ranging from 9 to 19% (the latter for the weak plume in a windy atmosphere). Overall, these discrepancies are in the range of observational uncertainty of column height. However, there are important differences amongst models in terms of local properties along the plume axis, particularly for the strong plume. Our analysis suggests that the simplified treatment of entrainment in 1D models is adequate to resolve the general behaviour of the weak plume. However, it is inadequate to capture complex features of the strong plume, such as large vortices, partial column collapse, or gravitational fountaining that strongly enhance entrainment in the lower atmosphere. We conclude that there is a need to more accurately quantify entrainment rates, improve the representation of plume radius, and incorporate the effects of column instability in future versions of 1D volcanic plume models.

A fast process development flow by applying design technology co-optimization

NASA Astrophysics Data System (ADS)

Chen, Yi-Chieh; Yeh, Shin-Shing; Ou, Tsong-Hua; Lin, Hung-Yu; Mai, Yung-Ching; Lin, Lawrence; Lai, Jun-Cheng; Lai, Ya Chieh; Xu, Wei; Hurat, Philippe

2017-03-01

Beyond 40 nm technology node, the pattern weak points and hotspot types increase dramatically. The typical patterns for lithography verification suffers huge turn-around-time (TAT) to handle the design complexity. Therefore, in order to speed up process development and increase pattern variety, accurate design guideline and realistic design combinations are required. This paper presented a flow for creating a cell-based layout, a lite realistic design, to early identify problematic patterns which will negatively affect the yield. A new random layout generating method, Design Technology Co-Optimization Pattern Generator (DTCO-PG), is reported in this paper to create cell-based design. DTCO-PG also includes how to characterize the randomness and fuzziness, so that it is able to build up the machine learning scheme which model could be trained by previous results, and then it generates patterns never seen in a lite design. This methodology not only increases pattern diversity but also finds out potential hotspot preliminarily. This paper also demonstrates an integrated flow from DTCO pattern generation to layout modification. Optical Proximity Correction, OPC and lithographic simulation is then applied to DTCO-PG design database to detect hotspots and then hotspots or weak points can be automatically fixed through the procedure or handled manually. This flow benefits the process evolution to have a faster development cycle time, more complexity pattern design, higher probability to find out potential hotspots in early stage, and a more holistic yield ramping operation.

Weak Fault Feature Extraction of Rolling Bearings Based on an Improved Kurtogram

PubMed Central

Chen, Xianglong; Feng, Fuzhou; Zhang, Bingzhi

2016-01-01

Kurtograms have been verified to be an efficient tool in bearing fault detection and diagnosis because of their superiority in extracting transient features. However, the short-time Fourier Transform is insufficient in time-frequency analysis and kurtosis is deficient in detecting cyclic transients. Those factors weaken the performance of the original kurtogram in extracting weak fault features. Correlated Kurtosis (CK) is then designed, as a more effective solution, in detecting cyclic transients. Redundant Second Generation Wavelet Packet Transform (RSGWPT) is deemed to be effective in capturing more detailed local time-frequency description of the signal, and restricting the frequency aliasing components of the analysis results. The authors in this manuscript, combining the CK with the RSGWPT, propose an improved kurtogram to extract weak fault features from bearing vibration signals. The analysis of simulation signals and real application cases demonstrate that the proposed method is relatively more accurate and effective in extracting weak fault features. PMID:27649171

Backward optical gain originating from weak localization strengthened three-photon process in Er/Yb co-doped (Pb,La)(Zr,Ti)O₃ ceramics.

PubMed

Xu, Caixia; Zhang, Jingwen; Zou, Yingyin K; Zhao, Hua

2016-03-21

The enhancement of green upconverted emission from the Er³⁺/Yb³⁺ co-doped (Pb,La)(Zr,Ti)O₃ ceramic powder under a pumping light with a wavelength of 1480 nm was observed to be greater than 30 times that from the bulk of the same sample. Weak localization of light supported by the spatial profile of scattered light facilitated the three-photon process contributing to stronger green upconverted emission. Significant backward light amplification was also observed and studied in detail. Additionally, the distribution of the localization zones in the sample was investigated using a probing laser beam with a wavelength of 532 nm. The findings in this work could be used in improving the solar cell efficiency, modulating color, and designing smart devices.

Comparative study on sample stacking by moving reaction boundary formed with weak acid and weak or strong base in capillary electrophoresis: II. Experiments.

PubMed

Zhang, Wei; Fan, Liuyin; Shao, Jing; Li, Si; Li, Shan; Cao, Chengxi

2011-04-15

To demonstrate the theoretic method on the stacking of zwitterion with moving reaction boundary (MRB) in the accompanying paper, the relevant experiments were performed. The experimental results quantitatively show that (1) MRB velocity, including the comparisons between MRB and zwitterionic velocities, possesses key importance to the design of MRB stacking; (2) a much long front alkaline plug without sample should be injected before the sample injection for a complete stacking of zwitterion if sample buffer is prepared with strong base, conversely no such plug is needed if using a weak base as the sample buffer with proper concentration and pH value; (3) the presence of salt in MRB system holds dramatic effect on the MRB stacking if sample solution is a strong base, but has no effect if a weak alkali is used as sample solution; (4) all of the experiments of this paper, including the previous work, quantitatively manifest the theory and predictions shown in the accompanying paper. In addition, the so-called derivative MRB-induced re-stacking and transient FASI-induced re-stacking were also observed during the experiments, and the relevant mechanisms were briefly demonstrated with the results. The theory and its calculation procedures developed in the accompanying paper can be well used for the predictions to the MRB stacking of zwitterion in CE. Copyright © 2011 Elsevier B.V. All rights reserved.

Two advertisements for TV drug ads.

PubMed

Bodenheimer, Thomas

2003-01-01

The paper by Joel Weissman and colleagues addresses the increasingly important topic of the effects of direct-to-consumer advertising (DTCA) by pharmaceutical companies. The authors claim that their results should be reassuring to "those concerned about potential adverse health care consequences of DTCA". However, the study and analysis of the data are marred by several flaws that diminish the importance and relevance of the findings, including weakness in design, overgenerous interpretations, and failure to address key questions. Rather than informing the debate, the study amounts to little more than an advertisement for drug advertisements.

Far-infrared spectrophotometer for astronomical observations

NASA Technical Reports Server (NTRS)

Moseley, H.; Silverberg, R. F.

1981-01-01

A liquid-helium-cooled far infrared spectrophotometer was built and used to make low resolution observations of the continua of several kinds of astronomical objects using the Kuiper Airborne Observatory. This instrument fills a gap in both sensitivity to continuum sources and spectral resolution between the broadband photometers with lambda/Delta lambda approximately 1 and spectrometers with lambda/Delta lambda greater than 50. While designed primarily to study planetary nebulae, the instrument permits study of the shape of the continua of many weak sources which cannot easily be observed with high resolution systems.

Mistletoe Extracts (PDQ)

MedlinePlus

... follow-up there was no increase in survival time in either the interferon or the mistletoe group. ... for patients, although this review had weaknesses in design and size. Quality of life and survival were ...

A Sparsity-Promoted Method Based on Majorization-Minimization for Weak Fault Feature Enhancement

PubMed Central

Hao, Yansong; Song, Liuyang; Tang, Gang; Yuan, Hongfang

2018-01-01

Fault transient impulses induced by faulty components in rotating machinery usually contain substantial interference. Fault features are comparatively weak in the initial fault stage, which renders fault diagnosis more difficult. In this case, a sparse representation method based on the Majorzation-Minimization (MM) algorithm is proposed to enhance weak fault features and extract the features from strong background noise. However, the traditional MM algorithm suffers from two issues, which are the choice of sparse basis and complicated calculations. To address these challenges, a modified MM algorithm is proposed in which a sparse optimization objective function is designed firstly. Inspired by the Basis Pursuit (BP) model, the optimization function integrates an impulsive feature-preserving factor and a penalty function factor. Second, a modified Majorization iterative method is applied to address the convex optimization problem of the designed function. A series of sparse coefficients can be achieved through iterating, which only contain transient components. It is noteworthy that there is no need to select the sparse basis in the proposed iterative method because it is fixed as a unit matrix. Then the reconstruction step is omitted, which can significantly increase detection efficiency. Eventually, envelope analysis of the sparse coefficients is performed to extract weak fault features. Simulated and experimental signals including bearings and gearboxes are employed to validate the effectiveness of the proposed method. In addition, comparisons are made to prove that the proposed method outperforms the traditional MM algorithm in terms of detection results and efficiency. PMID:29597280

A Sparsity-Promoted Method Based on Majorization-Minimization for Weak Fault Feature Enhancement.

PubMed

Ren, Bangyue; Hao, Yansong; Wang, Huaqing; Song, Liuyang; Tang, Gang; Yuan, Hongfang

2018-03-28

Fault transient impulses induced by faulty components in rotating machinery usually contain substantial interference. Fault features are comparatively weak in the initial fault stage, which renders fault diagnosis more difficult. In this case, a sparse representation method based on the Majorzation-Minimization (MM) algorithm is proposed to enhance weak fault features and extract the features from strong background noise. However, the traditional MM algorithm suffers from two issues, which are the choice of sparse basis and complicated calculations. To address these challenges, a modified MM algorithm is proposed in which a sparse optimization objective function is designed firstly. Inspired by the Basis Pursuit (BP) model, the optimization function integrates an impulsive feature-preserving factor and a penalty function factor. Second, a modified Majorization iterative method is applied to address the convex optimization problem of the designed function. A series of sparse coefficients can be achieved through iterating, which only contain transient components. It is noteworthy that there is no need to select the sparse basis in the proposed iterative method because it is fixed as a unit matrix. Then the reconstruction step is omitted, which can significantly increase detection efficiency. Eventually, envelope analysis of the sparse coefficients is performed to extract weak fault features. Simulated and experimental signals including bearings and gearboxes are employed to validate the effectiveness of the proposed method. In addition, comparisons are made to prove that the proposed method outperforms the traditional MM algorithm in terms of detection results and efficiency.

Approaches in Health Human Resource Forecasting: A Roadmap for Improvement

PubMed Central

Rafiei, Sima; Mohebbifar, Rafat; Hashemi, Fariba; Ezzatabadi, Mohammad Ranjbar; Farzianpour, Fereshteh

2016-01-01

Introduction Forecasting the demand and supply of health manpower in an accurate manner makes appropriate planning possible. The aim of this paper was to review approaches and methods for health manpower forecasting and consequently propose the features that improve the effectiveness of this important process of health manpower planning. Methods A literature review was conducted for studies published in English from 1990–2014 using Pub Med, Science Direct, Pro Quest, and Google Scholar databases. Review articles, qualitative studies, retrospective and prospective studies describing or applying various types of forecasting approaches and methods in health manpower forecasting were included in the review. The authors designed an extraction data sheet based on study questions to collect data on studies’ references, designs, and types of forecasting approaches, whether discussed or applied, with their strengths and weaknesses Results Forty studies were included in the review. As a result, two main categories of approaches (conceptual and analytical) for health manpower forecasting were identified. Each approach had several strengths and weaknesses. As a whole, most of them were faced with some challenges, such as being static and unable to capture dynamic variables in manpower forecasting and causal relationships. They also lacked the capacity to benefit from scenario making to assist policy makers in effective decision making. Conclusions An effective forecasting approach is supposed to resolve all the deficits that exist in current approaches and meet the key features found in the literature in order to develop an open system and a dynamic and comprehensive method necessary for today complex health care systems. PMID:27790343

CHAM: weak signals detection through a new multivariate algorithm for process control

NASA Astrophysics Data System (ADS)

Bergeret, François; Soual, Carole; Le Gratiet, B.

2016-10-01

Derivatives technologies based on core CMOS processes are significantly aggressive in term of design rules and process control requirements. Process control plan is a derived from Process Assumption (PA) calculations which result in a design rule based on known process variability capabilities, taking into account enough margin to be safe not only for yield but especially for reliability. Even though process assumptions are calculated with a 4 sigma known process capability margin, efficient and competitive designs are challenging the process especially for derivatives technologies in 40 and 28nm nodes. For wafer fab process control, PA are declined in monovariate (layer1 CD, layer2 CD, layer2 to layer1 overlay, layer3 CD etc….) control charts with appropriated specifications and control limits which all together are securing the silicon. This is so far working fine but such system is not really sensitive to weak signals coming from interactions of multiple key parameters (high layer2 CD combined with high layer3 CD as an example). CHAM is a software using an advanced statistical algorithm specifically designed to detect small signals, especially when there are many parameters to control and when the parameters can interact to create yield issues. In this presentation we will first present the CHAM algorithm, then the case-study on critical dimensions, with the results, and we will conclude on future work. This partnership between Ippon and STM is part of E450LMDAP, European project dedicated to metrology and lithography development for future technology nodes, especially 10nm.

Statistics of optical vortex wander on propagation through atmospheric turbulence.

PubMed

Gu, Yalong

2013-04-01

The transverse position of an optical vortex on propagation through atmospheric turbulence is studied. The probability density of the optical vortex position on a transverse plane in the atmosphere is formulated in weak turbulence by using the Born approximation. With these formulas, the effect of aperture averaging on topological charge detection is investigated. These results provide quantitative guidelines for the design of an optimal detector of topological charge, which has potential application in optical vortex communication systems.

Presenting a model for dynamic facial expression changes in detecting drivers' drowsiness.

PubMed

Karchani, Mohsen; Mazloumi, Adel; Saraji, Gebraeil Nasl; Gharagozlou, Faramarz; Nahvi, Ali; Haghighi, Khosro Sadeghniiat; Abadi, Bahador Makki; Foroshani, Abbas Rahimi

2015-01-01

Drowsiness while driving is a major cause of accidents. A driver fatigue detection system that is designed to sound an alarm, when appropriate, can prevent many accidents that sometime leads to the loss of life and property. In this paper, we classify drowsiness detection sensors and their strong and weak points. A compound model is proposed that uses image processing techniques to study the dynamic changes of the face to recognize drowsiness during driving.

Coal Mine Roadway Stability in Soft Rock: A Case Study

NASA Astrophysics Data System (ADS)

Shen, Baotang

2014-11-01

Roadway instability has always been a major concern in deep underground coal mines where the surrounding rock strata and coal seams are weak and the in situ stresses are high. Under the high overburden and tectonic stresses, roadways could collapse or experience excessive deformation, which not only endangers mining personnel but could also reduce the functionality of the roadway and halt production. This paper describes a case study on the stability of roadways in an underground coal mine in Shanxi Province, China. The mine was using a longwall method to extract coal at a depth of approximately 350 m. Both the coal seam and surrounding rock strata were extremely weak and vulnerable to weathering. Large roadway deformation and severe roadway instabilities had been experienced in the past, hence, an investigation of the roadway failure mechanism and new support designs were needed. This study started with an in situ stress measurement programme to determine the stress orientation and magnitude in the mine. It was found that the major horizontal stress was more than twice the vertical stress in the East-West direction, perpendicular to the gateroads of the longwall panel. The high horizontal stresses and low strength of coal and surrounding rock strata were the main causes of roadway instabilities. Detailed numerical modeling was conducted to evaluate the roadway stability and deformation under different roof support scenarios. Based on the modeling results, a new roadway support design was proposed, which included an optimal cable/bolt arrangement, full length grouting, and high pre-tensioning of bolts and cables. It was expected the new design could reduce the roadway deformation by 50 %. A field experiment using the new support design was carried out by the mine in a 100 m long roadway section. Detailed extensometry and stress monitorings were conducted in the experimental roadway section as well as sections using the old support design. The experimental section produced a much better roadway profile than the previous roadway sections. The monitoring data indicated that the roadway deformation in the experimental section was at least 40-50 % less than the previous sections. This case study demonstrated that through careful investigation and optimal support design, roadway stability in soft rock conditions can be significantly improved.

Impact of assistive technology on family caregivers of children with physical disabilities: a systematic review.

PubMed

Nicolson, Amy; Moir, Lois; Millsteed, Jeannine

2012-09-01

To systematically review the literature on the effects of assistive technology (AT) on family caregivers of children with physical disabilities. Electronic searches of Medline, CINAHL Plus, PubMed, and PsychInfo were conducted. The main search terms were AT, caregiver, physical disability, cerebral palsy and quality of life. Studies were included if they related to the impact of AT on the family caregiver of children with physical impairment. Data extraction and quality assessments were conducted by three reviewers. Five articles were eligible for inclusion. Two studies rated weak quality of evidence (level 5), two studies rated moderate quality of evidence (level 3), and one article was a systematic review, rating high level of quality (level 1). A paucity of literature, small sample sizes, descriptive study designs and weak methodological quality meant a narrative review was possible. Three articles reported that AT lightened caregiver assistance in the areas of mobility, self- care and social function. Evidence suggests that AT has a positive impact on children with physical impairments and their caregivers. Future studies in this area could include valid and reliable outcome measures of AT use and the psychological impacts of AT on caring for a child with physical impairments.

Making the First Cut: An Analysis of Academic Medicine Editors' Reasons for Not Sending Manuscripts Out for External Peer Review.

PubMed

Meyer, Holly S; Durning, Steven J; Sklar, David P; Maggio, Lauren A

2018-03-01

Manuscripts submitted to Academic Medicine (AM) undergo an internal editor review to determine whether they will be sent for external peer review. Increasingly, manuscripts are rejected at this early stage. This study seeks to inform scholars about common reasons for internal editor review rejections, increase transparency of the process, and provide suggestions for improving submissions. A mixed-methods approach was used to retrospectively analyze editors' free-text comments. Descriptive content analysis was performed of editors' comments for 369 manuscripts submitted between December 2014 and December 2015, and rejected prior to external peer review from AM. Comments were analyzed, categorized, and counted for explicit reasons for rejection. Nine categories of rejection reasons were identified: ineffective study question and/or design (338; 92%); suboptimal data collection process (180; 49%); weak discussion and/or conclusions (139; 37%); unimportant or irrelevant topic to the journal's mission (137; 37%); weak data analysis and/or presentation of results (120; 33%); text difficult to follow, to understand (89; 24%); inadequate or incomplete introduction (67; 18%); other publishing considerations (42; 11%); and issues with scientific conduct (20; 5%). Manuscripts had, on average, three or more reasons for rejection. Findings suggest that clear identification of a research question that is addressed by a well-designed study methodology on a topic aligned with the mission of the journal would address many of the problems that lead to rejection through the internal review process. The findings also align with research on external peer review.

How shall we design the future vehicle for Chinese market.

PubMed

Chen, Fang; Wang, Minjuan; Zhu, Xi Chan; Li, Jiaqi

2012-01-01

Surface transportation system is developing very fast in China and the number of vehicles is increasing quickly as well. This development creates a lot of problems on traffic safety and the number of accident is also increasing. In this paper, we made deep analysis of different possible causes of safety problems through three aspects: the traffic environment and infrastructure, in-vehicle information system design and the characteristics of drivers. There are many factors in each aspects may contribute to the transportation safety problems. Problems with infrastructure design and traffic design contribute over 50% of the traffic accident. Another important factor is that people has very little traffic safety concept and very weak on understanding the important of right behavior on the road. This paper has pointed the urgent needs to study the human factors in road and transportation system and vehicle HMI design, as there are very few such studies available in literature based on Chinese situation. The paper also proposed the needs to develop proactive educational system that can promote driver's understanding of traffic safety and to take the right action during drive.

Generation and associative encoding in young and old adults: the effect of the strength of association between cues and targets on a cued recall task.

PubMed

Taconnat, Laurence; Froger, Charlotte; Sacher, Mathilde; Isingrini, Michel

2008-01-01

The generation effect (i.e., better recall of the generated items than the read items) was investigated with a between-list design in young and elderly participants. The generation task difficulty was manipulated by varying the strength of association between cues and targets. Overall, strong associates were better recalled than weak associates. However, the results showed different generation effect patterns according to strength of association and age, with a greater generation effect for weak associates in younger adults only. These findings suggest that generating weak associates leads to more elaborated encoding, but that elderly adults cannot use this elaborated encoding as well as younger adults to recall the target words at test.

Colouring the Gaps in Learning Design: Aesthetics and the Visual in Learning

ERIC Educational Resources Information Center

Carroll, Fiona; Kop, Rita

2016-01-01

The visual is a dominant mode of information retrieval and understanding however, the focus on the visual dimension of Technology Enhanced Learning (TEL) is still quite weak in relation to its predominant focus on usability. To accommodate the future needs of the visual learner, designers of e-learning environments should advance the current…

Development of human factors guidelines for advanced traveler information systems and commercial vehicle operations : identification of the strengths and weaknesses of alternative information display formats

DOT National Transportation Integrated Search

1998-10-01

This report is one of a series produced as part of a contract designed to develop precise, detailed, human factors design guidelines for Advanced Traveler Information Systems (ATIS) and Commercial Vehicle Operations (CVO). The goals of the work cover...

Lessons Learned in Designing and Implementing a Computer-Adaptive Test for English

ERIC Educational Resources Information Center

Burston, Jack; Neophytou, Maro

2014-01-01

This paper describes the lessons learned in designing and implementing a computer-adaptive test (CAT) for English. The early identification of students with weak L2 English proficiency is of critical importance in university settings that have compulsory English language course graduation requirements. The most efficient means of diagnosing the L2…

78 FR 14080 - Kolcraft Enterprises, Inc., Provisional Acceptance of a Settlement Agreement and Order

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-04

..., and when a child pushes against the rail, the rail can unlatch unexpectedly, posing a fall hazard to... enforce a system of internal controls and procedures designed to ensure that: (i) Information required to... weaknesses in the design or operation of such internal controls that are reasonably likely to adversely...

Ergonomics intervention on an alternative design of a spinal board.

PubMed

Zadry, Hilma Raimona; Susanti, Lusi; Rahmayanti, Dina

2017-09-01

A spinal board is the evacuation tool of first aid to help the injured spinal cord. The existing spinal board has several weaknesses, both in terms of user comfort and the effectiveness and efficiency of the evacuation process. This study designs an ergonomic spinal board using the quality function deployment approach. A preliminary survey was conducted through direct observation and interviews with volunteers from the Indonesian Red Cross. Data gathered were translated into a questionnaire and answered by 47 participants in West Sumatra. The results indicate that the selection of materials, the application of strap systems as well as the addition of features are very important in designing an ergonomic spinal board. The data were used in designing an ergonomic spinal board. The use of anthropometric data ensures that this product can accommodate safety and comfort when immobilized, as well as the flexibility and speed of the rescue evacuation process.

Placebo effect in clinical trial design for irritable bowel syndrome.

PubMed

Shah, Eric; Pimentel, Mark

2014-04-30

Ongoing efforts to improve clinical trial design in irritable bowel syndrome have been hindered by high placebo response rates and ineffective outcome measures. We assessed established strategies to minimize placebo effect as well as the various ap-proaches to placebo effect which can affect trial design. These include genetic markers such as catechol-O-methyltransferase, opioidergic and dopaminergic neurobiologic theory, pre-cebo effect centered on expectancy theory, and side effect unblinding grounded on conditioning theory. We reviewed endpoints used in the study of IBS over the past decade including adequate relief and subjective global relief, emphasizing their weaknesses in fully evaluating the IBS condition, specifically their motility effects based on functional net value and relative benefit-harm based on dropouts due to adverse events. The focus of this review is to highlight ongoing efforts to improve clinical trial design which can lead to better outcomes in a real-world setting.

Effect of Contralateral Strength Training on Muscle Weakness in People With Multiple Sclerosis: Proof-of-Concept Case Series.

PubMed

Manca, Andrea; Cabboi, Maria Paola; Ortu, Enzo; Ginatempo, Francesca; Dragone, Daniele; Zarbo, Ignazio Roberto; de Natale, Edoardo Rosario; Mureddu, Giovanni; Bua, Guido; Deriu, Franca

2016-06-01

The contralateral strength training (CST) effect is a transfer of muscle performance to the untrained limb following training of the contralateral side. The aim of this study was to explore, in individuals with multiple sclerosis (MS) presenting marked lower limb strength asymmetry, the effectiveness of CST on management of muscle weakness of the more-affected limb following training of the less-affected limb. A single-subject research design was used. Eight individuals with MS underwent 16 to 18 high-intensity training sessions of the less-affected ankle dorsiflexor muscles. The primary outcome measure of this single-system case series was maximal strength expressed as peak moment and maximal work. Secondary outcome measures were: Six-Minute-Walk Test, Timed "Up & Go" Test, 10-Meter Timed Walk Test, and Multiple Sclerosis Quality of Life-54 questionnaire. After the 6-week intervention, the contralateral more affected (untrained) limb showed a 22% to 24% increase in maximal strength. From pretest-posttest measurements, participants also performed significantly better on the clinical and functional secondary outcome measures. At the 12-week follow-up, the strength levels of the weaker untrained limb remained significantly superior to baseline levels in the majority (5 out of 8) of the outcome parameters. Considering the design used, the absence of a control group, and the sample size, these findings should be cautiously generalized and will need confirmation in a properly planned randomized controlled trial. The present proof-of-concept study shows, for the first time, the occurrence of the CST effect on muscle performance of ankle dorsiflexor muscles in people with MS. These preliminary findings reveal new potential implications for CST as a promising rehabilitation approach to those conditions where unilateral muscle weakness does not allow or makes difficult performing conventional strength training of the weaker limb. © 2016 American Physical Therapy Association.

Nurse staffing impact on quality of care in nursing homes: a systematic review of longitudinal studies.

PubMed

Backhaus, Ramona; Verbeek, Hilde; van Rossum, Erik; Capezuti, Elizabeth; Hamers, Jan P H

2014-06-01

The relationship between nurse staffing and quality of care (QoC) in nursing homes continues to receive major attention. The evidence supporting this relationship, however, is weak because most studies employ a cross-sectional design. This review summarizes the findings from recent longitudinal studies. In April 2013, the databases PubMed, CINAHL, EMBASE, and PsycINFO were systematically searched. Studies were eligible if they (1) examined the relationship between nurse staffing and QoC outcomes, (2) included only nursing home data, (3) were original research articles describing quantitative, longitudinal studies, and (4) were written in English, Dutch, or German. The methodological quality of 20 studies was assessed using the Newcastle-Ottawa scale, excluding 2 low-quality articles for the analysis. No consistent relationship was found between nurse staffing and QoC. Higher staffing levels were associated with better as well as lower QoC indicators. For example, for restraint use both positive (ie, less restraint use) and negative outcomes (ie, more restraint use) were found. With regard to pressure ulcers, we found that more staff led to fewer pressure ulcers and, therefore, better results, no matter who (registered nurse, licensed practical nurse/ licensed vocational nurse, or nurse assistant) delivered care. No consistent evidence was found for a positive relationship between staffing and QoC. Although some positive indications were suggested, major methodological and theoretical weaknesses (eg, timing of data collection, assumed linear relationship between staffing and QoC) limit interpretation of results. Our findings demonstrate the necessity for well-designed longitudinal studies to gain a better insight into the relationship between nurse staffing and QoC in nursing homes. Copyright © 2014 American Medical Directors Association, Inc. Published by Elsevier Inc. All rights reserved.

Molecules Designed to Contain Two Weakly Coupled Spins with a Photoswitchable Spacer.

PubMed

Uber, Jorge Salinas; Estrader, Marta; Garcia, Jordi; Lloyd-Williams, Paul; Sadurní, Anna; Dengler, Dominik; van Slageren, Joris; Chilton, Nicholas F; Roubeau, Olivier; Teat, Simon J; Ribas-Ariño, Jordi; Aromí, Guillem

2017-10-04

Controlling the charges and spins of molecules lies at the heart of spintronics. A photoswitchable molecule consisting of two independent spins separated by a photoswitchable moiety was designed in the form of new ligand H 4 L, which features a dithienylethene photochromic unit and two lateral coordinating moieties, and yields molecules with [MM⋅⋅⋅MM] topology. Compounds [M 4 L 2 (py) 6 ] (M=Cu, 1; Co, 2; Ni, 3; Zn, 4) were prepared and studied by single-crystal X-ray diffraction (SCXRD). Different metal centers can be selectively distributed among the two chemically distinct sites of the ligand, and this enables the preparation of many double-spin systems. Heterometallic [MM'⋅⋅⋅M'M] analogues with formulas [Cu 2 Ni 2 L 2 (py) 6 ] (5), [Co 2 Ni 2 L 2 (py) 6 ] (6), [Co 2 Cu 2 L 2 (py) 6 ] (7), [Cu 2 Zn 2 L 2 (py) 6 ] (8), and [Ni 2 Zn 2 L 2 (py) 6 ] (9) were prepared and analyzed by SCXRD. Their composition was established unambiguously. All complexes exhibit two weakly interacting [MM'] moieties, some of which embody two-level quantum systems. Compounds 5 and 8 each exhibit a pair of weakly coupled S=1/2 spins that show quantum coherence in pulsed Q-band EPR spectroscopy, as required for quantum computing, with good phase memory times (T M =3.59 and 6.03 μs at 7 K). Reversible photoswitching of all the molecules was confirmed in solution. DFT calculations on 5 indicate that the interaction between the two spins of the molecule can be switched on and off on photocyclization. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Predictors of Depression Stigma in Medical Students: Potential Targets for Prevention and Education.

PubMed

Wimsatt, Leslie A; Schwenk, Thomas L; Sen, Ananda

2015-11-01

Suicide rates are higher among U.S. physicians than the general population. Untreated depression is a major risk factor, yet depression stigma presents a barrier to treatment. This study aims to identify early career indications of stigma among physicians-in-training and to inform the design of stigma-reduction programs. A cross-sectional student survey administered at a large, Midwestern medical school in fall 2009 included measures of depression symptoms, attitudes toward mental health, and potential sources of depression stigma. Principal components factor analysis and linear regression were used to examine stigma factors associated with depression in medical students. The response rate was 65.7%, with 14.7% students reporting a previous depression diagnosis. Most students indicated that, if depressed, they would feel embarrassed if classmates knew. Many believed that revealing depression could negatively affect professional advancement. Factor analyses revealed three underlying stigma constructs: personal weakness, public devaluation, and social/professional discrimination. Students associating personal weakness with depression perceived medication as less efficacious and the academic environment as more competitive. Those endorsing public stigma viewed medication and counseling as less efficacious and associated depression with an inability to cope. Race, gender, and diagnosis of past/current depression also related to beliefs about stigma. Depression measures most strongly predicted stigma associated with personal weakness and social/professional discrimination. Recommendations for decreasing stigma among physicians-in-training include consideration of workplace perceptions, depression etiology, treatment efficacy, and personal attributes in the design of stigma reduction programs that could facilitate help-seeking behavior among physicians throughout their career. Copyright © 2015 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Achieving Weak Light Response with Plasmonic Nanogold-Decorated Organic Phototransistors.

PubMed

Luo, Xiao; Du, Lili; Liang, Yuanlong; Zhao, Feiyu; Lv, Wenli; Xu, Kun; Wang, Ying; Peng, Yingquan

2018-05-09

Weak light response of organic photodetectors has fascinating potentials in fields of modern science and technology. However, their photoresponsivity is hindered by poor photocarrier excitation and transport. Decorating active-layer surface with plasmonic nanometals is considered a viable strategy to address this issue. Here, we demonstrate a plasmonic nanogold decorated organic phototransistor achieving remarkable enhancement of photoresponsivity. Meanwhile, the photoresponsive range is broadened by 4 orders of magnitude. The proposed design is substantiated by a schematic energy level model combined with theoretical simulation analysis, enabling the development of the advanced optoelectronics.

Advanced reliability modeling of fault-tolerant computer-based systems

NASA Technical Reports Server (NTRS)

Bavuso, S. J.

1982-01-01

Two methodologies for the reliability assessment of fault tolerant digital computer based systems are discussed. The computer-aided reliability estimation 3 (CARE 3) and gate logic software simulation (GLOSS) are assessment technologies that were developed to mitigate a serious weakness in the design and evaluation process of ultrareliable digital systems. The weak link is based on the unavailability of a sufficiently powerful modeling technique for comparing the stochastic attributes of one system against others. Some of the more interesting attributes are reliability, system survival, safety, and mission success.

Horizontal axis wind turbine post stall airfoil characteristics synthesization

NASA Technical Reports Server (NTRS)

Tangler, James L.; Ostowari, Cyrus

1995-01-01

Blade-element/momentum performance prediction codes are routinely used for wind turbine design and analysis. A weakness of these codes is their inability to consistently predict peak power upon which the machine structural design and cost are strongly dependent. The purpose of this study was to compare post-stall airfoil characteristics synthesization theory to a systematically acquired wind tunnel data set in which the effects of aspect ratio, airfoil thickness, and Reynolds number were investigated. The results of this comparison identified discrepancies between current theory and the wind tunnel data which could not be resolved. Other factors not previously investigated may account for these discrepancies and have a significant effect on peak power prediction.

What quantum measurements measure

NASA Astrophysics Data System (ADS)

Griffiths, Robert B.

2017-09-01

A solution to the second measurement problem, determining what prior microscopic properties can be inferred from measurement outcomes ("pointer positions"), is worked out for projective and generalized (POVM) measurements, using consistent histories. The result supports the idea that equipment properly designed and calibrated reveals the properties it was designed to measure. Applications include Einstein's hemisphere and Wheeler's delayed choice paradoxes, and a method for analyzing weak measurements without recourse to weak values. Quantum measurements are noncontextual in the original sense employed by Bell and Mermin: if [A ,B ]=[A ,C ]=0 ,[B ,C ]≠0 , the outcome of an A measurement does not depend on whether it is measured with B or with C . An application to Bohm's model of the Einstein-Podolsky-Rosen situation suggests that a faulty understanding of quantum measurements is at the root of this paradox.

Extended producer responsibility for consumer waste: the gap between economic theory and implementation.

PubMed

Dubois, Maarten

2012-09-01

Although economic theory supports the use of extended producer responsibility (EPR) to stimulate prevention and recycling of waste, EPR systems implemented in Europe are often criticized as a result of weak incentives for prevention and green product design. Using a stylized economic model, this article evaluates the efficiency of European EPR systems. The model reveals that the introduction of static collection targets creates a gap between theory and implementation. Static targets lead to inefficient market outcomes and weak incentives for prevention and green product design. The minimum collection targets should be complemented with a tax on producers for the non-collected waste fraction. Because such a tax internalizes the cost of waste disposal, more efficient price signals will lead to better incentives for waste management in a complex and dynamic market.

Design of tablets for the delayed and complete release of poorly water-soluble weak base drugs using SBE7M-β-CD as a solubilizing agent.

PubMed

Rao, Venkatramana M; Zannou, Erika A; Stella, Valentino J

2011-04-01

The challenge of designing a delayed-release oral dosage form is significantly increased when the drug substance is poorly water soluble. This manuscript describes the design and characterization of a novel controlled-release film-coated tablet for the pH-triggered delayed and complete release of poorly water-soluble weak base drugs. Delivery of weak bases is specifically highlighted with the use of dipyridamole and prazosin as model compounds. Tailored delayed release is achieved with a combination of an insoluble but semipermeable polymer and an enteric polymer, such as cellulose acetate and hydroxypropyl cellulose phthalate, respectively, as coatings. The extent of the time lag prior to complete release depends on the film-coating composition and thickness. Complete release is achieved by the addition of a cyclodextrin, namely SBE7M-β-CD with or without a pH modifier added to the tablet core to ensure complete solubilization and release of the drug substance. The film-coating properties allow the complex formation/solubilization to occur in situ. Additionally, the drug release rate can be modulated on the basis of the cyclodextrin to drug molar ratio. This approach offers a platform technology for delayed release of potent but poorly soluble drugs and the release can be modulated by adjusting the film-coating composition and thickness and/or the cyclodextrin and pH modifier, if necessary. Copyright © 2010 Wiley-Liss, Inc.

Design Evolution: From Rolling Piston to Revolving Vane to Cross-Vane Expander-compressor unit

NASA Astrophysics Data System (ADS)

T, K.; S, Yap K.

2015-08-01

In this paper the design evolution from rolling piston compressor (RP) to revolving vane compressor (RV) and finally to cross-vane expander-compressor unit (CVEC) is presented and discussed. The details in the design philosophy which initiated this evolution will be presented and discussed. It is estimated that more than 90% of the room air-conditioners uses RP in its compressor. This is because of its advantages: it has the few parts, it is simple geometrically and it is reliable. However, it is with no weaknesses. RP's weaknesses lie in three parts: too many rubbing surfaces with high relative rubbing velocity with each other which give rise to high frictional losses; components (eccentric and roller) are not rotating at their centres and resulted in unnecessary inherent vibration; vane tip is constantly rubbing against the roller making it a weakest part in design. To overcome RP's weaknesses, RV is introduced. As compared to RP, RV has fewer rubbing surfaces, and the relative velocities among these surfaces are reduced Components in RV rotate at their own centres and there is no inherent vibration; the rubbing at the vane tip has been eliminated completely. However, like RP, RV also has a large rotor which occupied "useful" space and making the working chamber relatively small. To overcome this latter problem, CVEC is introduced. In this newly invented CVCE, not only parts are all concentric and rotate at their own centres, the unit also recovers expansion energy and hence significantly reduces energy required by the refrigeration systems. And, more importantly, all these are carried out not at the expense of the additional cost. In this paper, details on these three compressors are explained, compared and their respective uniqueness are shown and discussed.

How the Weak Variance of Momentum Can Turn Out to be Negative

NASA Astrophysics Data System (ADS)

Feyereisen, M. R.

2015-05-01

Weak values are average quantities, therefore investigating their associated variance is crucial in understanding their place in quantum mechanics. We develop the concept of a position-postselected weak variance of momentum as cohesively as possible, building primarily on material from Moyal (Mathematical Proceedings of the Cambridge Philosophical Society, Cambridge University Press, Cambridge, 1949) and Sonego (Found Phys 21(10):1135, 1991) . The weak variance is defined in terms of the Wigner function, using a standard construction from probability theory. We show this corresponds to a measurable quantity, which is not itself a weak value. It also leads naturally to a connection between the imaginary part of the weak value of momentum and the quantum potential. We study how the negativity of the Wigner function causes negative weak variances, and the implications this has on a class of `subquantum' theories. We also discuss the role of weak variances in studying determinism, deriving the classical limit from a variational principle.

Presenting a model for dynamic facial expression changes in detecting drivers’ drowsiness

PubMed Central

Karchani, Mohsen; Mazloumi, Adel; Saraji, Gebraeil Nasl; Gharagozlou, Faramarz; Nahvi, Ali; Haghighi, Khosro Sadeghniiat; Abadi, Bahador Makki; Foroshani, Abbas Rahimi

2015-01-01

Drowsiness while driving is a major cause of accidents. A driver fatigue detection system that is designed to sound an alarm, when appropriate, can prevent many accidents that sometime leads to the loss of life and property. In this paper, we classify drowsiness detection sensors and their strong and weak points. A compound model is proposed that uses image processing techniques to study the dynamic changes of the face to recognize drowsiness during driving. PMID:26120417

An examination of Aikido's Fourth Teaching: an anatomical study of the tissues of the forearm.

PubMed

Olson, G D; Seitz, F C

1990-12-01

One of the basic teachings of Aikido is known as Yonkyo (Fourth Teaching) or Tekubi-Osae (Wrist Securing). According to some Aikido master teachers, Yonkyo is designed to attack the opponent's weak points. This investigation focused on examining this teaching with the purpose of describing the anatomical tissues involved in the etiology of pain when this teaching is applied precisely. Particular focus was placed on the anatomical locations/sources of pain associated with the application of this teaching.

Correlation of the apparent diffusion coefficient and the standardized uptake value in neoplastic lesions: a meta-analysis.

PubMed

Shen, Guohua; Ma, Huan; Liu, Bin; Ren, Pengwei; Kuang, Anren

2017-12-01

Diffusion-weighted imaging and fluorine-18-fluorodeoxyglucose PET are increasingly being recognized as feasible oncological techniques. The apparent diffusion coefficient (ADC) measured by diffusion-weighted imaging and the standardized uptake value (SUV) from fluorine-18-fluorodeoxyglucose PET have similar clinical applications. The aim of this study was to assess the correlation between these two parameters in various cancers. Several major databases were searched for eligible studies. The correlation coefficient (ρ) values were pooled in a random-effects model. Begg's test was used to analyze the existence of publication bias and the sources of heterogeneity were explored in subgroup analyses on the basis of study design, diagnostic method, scanning modality, and tumor type. Thirty-five articles were accepted. The pooled ρ value of all of the accepted studies was -0.30 (95% confidence interval: -0.33 to -0.27), and notable heterogeneity was present (I=69.4%, P<0.001), which indicated a relatively weak negative correlation. The pooled ρ values were -0.26, -0.33, -0.32, and -0.33 for the SUVmax/ADCmean, SUVmax/ADCmin, SUVmean/ADCmean, and SUVmean/ADCmin relationships, respectively. The study design and diagnostic method were potential sources of heterogeneity. Lung cancer showed a stronger correlation (ρ=-0.42) than head and neck cancer (ρ=-0.27), cervical cancer (ρ=-0.21), and breast cancer (ρ=-0.23). A Begg's test indicated no significant publication bias among the accepted studies (P>0.05). The two functional parameters of ADC and SUV showed a very weak inverse correlation, which may contribute toward a sophisticated characterization of tumor biology. However, the findings require further validation with trials with large samples and different tumor types.

Method and apparatus for evaluating structural weakness in polymer matrix composites

DOEpatents

Wachter, E.A.; Fisher, W.G.

1996-01-09

A method and apparatus for evaluating structural weaknesses in polymer matrix composites is described. An object to be studied is illuminated with laser radiation and fluorescence emanating therefrom is collected and filtered. The fluorescence is then imaged and the image is studied to determine fluorescence intensity over the surface of the object being studied and the wavelength of maximum fluorescent intensity. Such images provide a map of the structural integrity of the part being studied and weaknesses, particularly weaknesses created by exposure of the object to heat, are readily visible in the image. 6 figs.

Method and apparatus for evaluating structural weakness in polymer matrix composites

DOEpatents

Wachter, Eric A.; Fisher, Walter G.

1996-01-01

A method and apparatus for evaluating structural weaknesses in polymer matrix composites is described. An object to be studied is illuminated with laser radiation and fluorescence emanating therefrom is collected and filtered. The fluorescence is then imaged and the image is studied to determine fluorescence intensity over the surface of the object being studied and the wavelength of maximum fluorescent intensity. Such images provide a map of the structural integrity of the part being studied and weaknesses, particularly weaknesses created by exposure of the object to heat, are readily visible in the image.

Weakly Ionized Plasmas in Hypersonics: Fundamental Kinetics and Flight Applications

NASA Astrophysics Data System (ADS)

Macheret, Sergey

2005-05-01

The paper reviews some of the recent studies of applications of weakly ionized plasmas to supersonic/hypersonic flight. Plasmas can be used simply as means of delivering energy (heating) to the flow, and also for electromagnetic flow control and magnetohydrodynamic (MHD) power generation. Plasma and MHD control can be especially effective in transient off-design flight regimes. In cold air flow, nonequilibrium plasmas must be created, and the ionization power budget determines design, performance envelope, and the very practicality of plasma/MHD devices. The minimum power budget is provided by electron beams and repetitive high-voltage nanosecond pulses, and the paper describes theoretical and computational modeling of plasmas created by the beams and repetitive pulses. The models include coupled equations for non-local and unsteady electron energy distribution function (modeled in forward-back approximation), plasma kinetics, and electric field. Recent experimental studies at Princeton University have successfully demonstrated stable diffuse plasmas sustained by repetitive nanosecond pulses in supersonic air flow, and for the first time have demonstrated the existence of MHD effects in such plasmas. Cold-air hypersonic MHD devices are shown to permit optimization of scramjet inlets at Mach numbers higher than the design value, while operating in self-powered regime. Plasma energy addition upstream of the inlet throat can increase the thrust by capturing more air (Virtual Cowl), or it can reduce the flow Mach number and thus eliminate the need for an isolator duct. In the latter two cases, the power that needs to be supplied to the plasma would be generated by an MHD generator downstream of the combustor, thus forming the "reverse energy bypass" scheme. MHD power generation on board reentry vehicles is also discussed.

Baseline scheme for polarization preservation and control in the MEIC ion complex

DOE Office of Scientific and Technical Information (OSTI.GOV)

Derbenev, Yaroslav S.; Lin, Fanglei; Morozov, Vasiliy

2015-09-01

The scheme for preservation and control of the ion polarization in the Medium-energy Electron-Ion Collider (MEIC) has been under active development in recent years. The figure-8 configuration of the ion rings provides a unique capability to control the polarization of any ion species including deuterons by means of "weak" solenoids rotating the particle spins by small angles. Insertion of "weak" solenoids into the magnetic lattices of the booster and collider rings solves the problem of polarization preservation during acceleration of the ion beam. Universal 3D spin rotators designed on the basis of "weak" solenoids allow one to obtain any polarizationmore » orientation at an interaction point of MEIC. This paper presents the baseline scheme for polarization preservation and control in the MEIC ion complex.« less

Student error patterns as a function of curriculum design: teaching fractions to remedial high school students and high school students with learning disabilities.

PubMed

Kelly, B; Gersten, R; Carnine, D

1990-01-01

This study evaluated the relative effectiveness of a curriculum that incorporated three empirically derived principles of curriculum design with a basal approach in teaching basic fractions concepts to students with learning disabilities and other low performing students in high school remedial math classes. The components of effective mathematics instruction articulated by Good and Grouws (1979) were implemented in both conditions. Thus, the curriculum design variables were isolated by keeping all other aspects of instruction constant. Results indicated that, although both programs were reasonably successful in teaching the material, the curriculum program utilizing sophisticated principles of curriculum design was significantly more effective. Mean scores on a curriculum-referenced test were 96.5% for that group and 82.3% for the basal group. Secondary analyses of item clusters revealed that areas of weakness in the performance of the basal group could be directly linked to hypothesized flaws in its curriculum design.

Overview of clinical research design.

PubMed

Hartung, Daniel M; Touchette, Daniel

2009-02-15

Basic concepts and terminology of clinical research design are presented for new clinical investigators. Clinical research, research involving human subjects, can be described as either observational or experimental. The findings of all clinical research can be threatened by issues of bias and confounding. Biases are systematic errors in how study subjects are selected or measured, which result in false inferences. Confounding is a distortion in findings that is attributable to mixing variable effects. Uncontrolled observation research is generally more prone to bias and confounding than experimental research. Observational research includes designs such as the cohort study, case-control study, and cross-sectional study, while experimental research typically involves a randomized controlled trial (RCT). The cohort study, which includes the RCT, defines subject allocation on the basis of exposure interest (e.g., drug, disease-management program) and follows the patients to assess the outcomes. The case-control study uses the primary outcome of interest (e.g., adverse event) to define subject allocation, and different exposures are assessed in a retrospective manner. Cross-sectional research evaluates both exposure and outcome concurrently. Each of these design methods possesses different strengths and weaknesses in answering research questions, as well as underlying many study subtypes. While experimental research is the strongest method for establishing causality, it can be difficult to accomplish under many scenarios. Observational clinical research offers many design alternatives that may be appropriate if planned and executed carefully.

SNAP (Space Nuclear Auxiliary Power) reactor overview. Final report, June 1982-December 1983

DOE Office of Scientific and Technical Information (OSTI.GOV)

Voss, S.S.

1984-08-01

The SNAP reactor programs are outlined in this report. A summary of the program is included along with a technical outline of the SER, S2DR, SNAP 10A/SNAPSHOT, S8ER, and S8DR reactor systems. Specifications of the designs, the design logic and a conclusion outlining some of the program weaknesses are given.

Contagion processes on the static and activity-driven coupling networks

NASA Astrophysics Data System (ADS)

Lei, Yanjun; Jiang, Xin; Guo, Quantong; Ma, Yifang; Li, Meng; Zheng, Zhiming

2016-03-01

The evolution of network structure and the spreading of epidemic are common coexistent dynamical processes. In most cases, network structure is treated as either static or time-varying, supposing the whole network is observed in the same time window. In this paper, we consider the epidemics spreading on a network which has both static and time-varying structures. Meanwhile, the time-varying part and the epidemic spreading are supposed to be of the same time scale. We introduce a static and activity-driven coupling (SADC) network model to characterize the coupling between the static ("strong") structure and the dynamic ("weak") structure. Epidemic thresholds of the SIS and SIR models are studied using the SADC model both analytically and numerically under various coupling strategies, where the strong structure is of homogeneous or heterogeneous degree distribution. Theoretical thresholds obtained from the SADC model can both recover and generalize the classical results in static and time-varying networks. It is demonstrated that a weak structure might make the epidemic threshold low in homogeneous networks but high in heterogeneous cases. Furthermore, we show that the weak structure has a substantive effect on the outbreak of the epidemics. This result might be useful in designing some efficient control strategies for epidemics spreading in networks.

Raman spectra of adsorbed layers on space shuttle and AOTV thermal protection system surface

NASA Technical Reports Server (NTRS)

Willey, Ronald J.

1987-01-01

Surfaces of interest to space vehicle heat shield design were struck by a 2 W argon ion laser line while subjected to supersonic arc jet flow conditions. Emission spectra were taken at 90 deg to the angle of laser incidence on the test object. Results showed possible weak Raman shifts which could not be directly tied to any particular parameter such as surface temperature or gas composition. The investigation must be considered exploratory in terms of findings. Many undesirable effects were found and corrected as the project progressed. For instance, initial spectra settings led to ghosts which were eliminated by closing the intermediate of filter slit of the Spex from 8 to 3 mm. Further, under certain conditions, plasma lines from the laser were observed. Several materials were also investigated at room temperature for Raman shifts. Results showed Raman shifts for RCC and TEOS coated materials. The HRSI materials showed only weak Raman shifts, however, substantial efforts were made in studying these materials. Baseline materials showed the technique to be sound. The original goal was to find a Raman shift for the High-temperature Reusable Surface Insulation (HRSI) Reaction Cured borosilicate Glass (RCG) coated material and tie the amplitude of this peak to Arc jet conditions. Weak Raman shifts may be present, however, time limitations prevented confirmation.

Comparison of three strong ion models used for quantifying the acid-base status of human plasma with special emphasis on the plasma weak acids.

PubMed

Anstey, Chris M

2005-06-01

Currently, three strong ion models exist for the determination of plasma pH. Mathematically, they vary in their treatment of weak acids, and this study was designed to determine whether any significant differences exist in the simulated performance of these models. The models were subjected to a "metabolic" stress either in the form of variable strong ion difference and fixed weak acid effect, or vice versa, and compared over the range 25 < or = Pco(2) < or = 135 Torr. The predictive equations for each model were iteratively solved for pH at each Pco(2) step, and the results were plotted as a series of log(Pco(2))-pH titration curves. The results were analyzed for linearity by using ordinary least squares regression and for collinearity by using correlation. In every case, the results revealed a linear relationship between log(Pco(2)) and pH over the range 6.8 < or = pH < or = 7.8, and no significant difference between the curve predictions under metabolic stress. The curves were statistically collinear. Ultimately, their clinical utility will be determined both by acceptance of the strong ion framework for describing acid-base physiology and by the ease of measurement of the independent model parameters.

Twenty-four-hour esophageal impedance-pH monitoring in healthy preterm neonates: rate and characteristics of acid, weakly acidic, and weakly alkaline gastroesophageal reflux.

PubMed

López-Alonso, Manuel; Moya, Maria Jose; Cabo, Jose Antonio; Ribas, Juan; del Carmen Macías, Maria; Silny, Jiry; Sifrim, Daniel

2006-08-01

Gastroesophageal reflux is a physiologic process and is considered pathologic (gastroesophageal reflux disease) when it causes symptoms or results in complications. It is common in preterm infants and occurs in healthy neonates. Twenty-four-hour pH monitoring commonly is used in children for diagnosis of gastroesophageal reflux disease, and abnormal reflux is considered with detection of increased esophageal acid exposure. However, in neonates, relatively few gastroesophageal reflux episodes cause esophageal acidification to pH < 4. Premature infants receive frequent feeds, which can induce a weaker acid secretory response than that observed in older infants and adults. As a consequence, gastric pH may be > 4 for prolonged periods, and reflux of gastric contents might be less acidic or even alkaline. Esophageal impedance monitoring can detect weakly acidic and even alkaline gastroesophageal reflux. The role of weakly acidic reflux in the pathophysiology of gastroesophageal reflux disease in preterm infants is not clear. To date, studies that have used impedance-pH in neonates assessed the association between nonacid reflux and cardiorespiratory symptoms, but no impedance data from healthy preterm neonates have been available to determine whether those symptomatic neonates had an increased number of weakly acidic reflux episodes or increased reactivity to a physiologic number of reflux events. Our aim with this study was to provide impedance-pH values for acid, weakly acidic, and weakly alkaline reflux from healthy preterm neonates. Esophageal impedance was recorded for 24 hours in 21 asymptomatic preterm neonates by replacing the conventional feeding tube with a specially designed feeding tube that included 9 impedance electrodes (8 French). All neonates were asymptomatic, with spontaneous breathing. Reflux monitoring was performed after comprehensive explanation and on receipt of written parental consent. Esophageal and gastric pH were monitored using a separate parallel pediatric catheter (6 French). According to the corresponding pH change, impedance-detected reflux was classified as acid, weakly acidic, and weakly alkaline. For each infant, the total number of reflux events, the acid exposure and bolus exposure times at 2 cm above the respiratory inversion point, and average proximal extent of reflux were calculated. Twenty-six preterm neonates were recruited into this study. A preliminary analysis was performed, and tracings were classified according to their quality and the presence of technical artifacts (spontaneous pH and impedance drifts, esophageal probe migration, and dysfunction of 1 or more impedance channels). Five studies were excluded because of 1 or more technical artifacts; a total of 21 neonates represent the final cohort included. At birth, the infants had a median postmenstrual age of 32 weeks, and the measurements were performed at a median age of 12 days. The total recording time was 23.7 +/- 2 hours. Gastric pH was higher than 4 during 69.3 +/- 20.4% of the recording time. The median number of reflux events in 24 hours was 71, 25.4% (range: 0%-53.1%) of which were acid, 72.9% (range: 45.3%-98.0%) were weakly acidic, and 0% (range: 0%-8.1%) were weakly alkaline. Compared with fasting periods, feeding periods tended to be associated with a higher number of total reflux events per hour. The acidity of reflux, however, was significantly different: during fasting, the number of acid reflux episodes per hour was higher, whereas during feeding, the number of weakly acidic reflux episodes was increased. Most reflux events were only liquid, whereas gas was present either mixed with liquid or pure only in 7.7% of all reflux episodes detected. The proximal esophageal segments were reached in 90% of reflux episodes. Reflux-related acid exposure (pH drops associated with impedance-detected reflux) was 1.66% (range: 0%-6.43%), whereas total acid exposure (associated and not associated with reflux detected by impedance) was 5.59% (range: 0.04%-20.69%). There was no relationship between the number or acidity of reflux events and anthropometric parameters such as weight and gestational age. We present the first study using 24-hour impedance-pH recordings in asymptomatic premature neonates. Previous studies that used pH-metry suggested that neonatal cardiorespiratory symptoms could be related to acid gastroesophageal reflux. However, pH-metry could not detect accurately weakly acidic or nonacid reflux. Our healthy premature neonates had approximately 70 reflux events in 24 hours, 25% of which were acid, 73% were weakly acidic, and 2% were weakly alkaline. The number of reflux events per hour (2-3 per hour) was slightly lower than that described in premature neonates with cardiorespiratory events (4 per hour). We confirmed that weakly acidic reflux is more prevalent than acid reflux, particularly so during the feeding periods. In contrast, similar to healthy adults, weakly alkaline reflux was very rare. We confirmed findings from previous studies in which most reflux events were pure liquid during both fasting and during postprandial periods and gas reflux was very rare. As in neonates with cardiorespiratory symptoms, the majority of reflux events in asymptomatic preterms reached the proximal esophagus or pharynx, and there were no differences between acid and weakly acidic reflux. The lack of differences between asymptomatic and diseased infants contravenes the hypothesis for macro- or microaspiration but does not exclude hypersensitivity to reflux as a cause for respiratory symptoms. The acid exposure that was related to reflux events and detected by impedance was significantly lower than the total acid exposure during 24 hours. Increased acid exposure could be attributable to pH-only reflux events or, less frequently, to slow drifts of pH from baselines at approximately 5 to values < 4. These changes were not accompanied by a typical impedance pattern of reflux but by slow drifts in impedance in 1 or 2 channels. Our findings confirm the need for the use of impedance together with pH-metry for diagnosis of all gastroesophageal reflux events. The relationship between gastroesophageal reflux and cardiorespiratory events in neonates and older infants has been studied extensively. The current evidence for such a relationship is controversial. This study provides values of impedance-pH monitoring for acid, weakly acidic, and weakly alkaline reflux from healthy preterm neonates that can be used for comparison when evaluating gastroesophageal reflux in preterm infants with a cardiorespiratory disease.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Quon, Eliot; Platt, Andrew; Yu, Yi-Hsiang

Extreme loads are often a key cost driver for wave energy converters (WECs). As an alternative to exhaustive Monte Carlo or long-term simulations, the most likely extreme response (MLER) method allows mid- and high-fidelity simulations to be used more efficiently in evaluating WEC response to events at the edges of the design envelope, and is therefore applicable to system design analysis. The study discussed in this paper applies the MLER method to investigate the maximum heave, pitch, and surge force of a point absorber WEC. Most likely extreme waves were obtained from a set of wave statistics data based onmore » spectral analysis and the response amplitude operators (RAOs) of the floating body; the RAOs were computed from a simple radiation-and-diffraction-theory-based numerical model. A weakly nonlinear numerical method and a computational fluid dynamics (CFD) method were then applied to compute the short-term response to the MLER wave. Effects of nonlinear wave and floating body interaction on the WEC under the anticipated 100-year waves were examined by comparing the results from the linearly superimposed RAOs, the weakly nonlinear model, and CFD simulations. Overall, the MLER method was successfully applied. In particular, when coupled to a high-fidelity CFD analysis, the nonlinear fluid dynamics can be readily captured.« less

Quantum control and measurement of atomic spins in polarization spectroscopy

NASA Astrophysics Data System (ADS)

Deutsch, Ivan H.; Jessen, Poul S.

2010-03-01

Quantum control and measurement are two sides of the same coin. To affect a dynamical map, well-designed time-dependent control fields must be applied to the system of interest. To read out the quantum state, information about the system must be transferred to a probe field. We study a particular example of this dual action in the context of quantum control and measurement of atomic spins through the light-shift interaction with an off-resonant optical probe. By introducing an irreducible tensor decomposition, we identify the coupling of the Stokes vector of the light field with moments of the atomic spin state. This shows how polarization spectroscopy can be used for continuous weak measurement of atomic observables that evolve as a function of time. Simultaneously, the state-dependent light shift induced by the probe field can drive nonlinear dynamics of the spin, and can be used to generate arbitrary unitary transformations on the atoms. We revisit the derivation of the master equation in order to give a unified description of spin dynamics in the presence of both nonlinear dynamics and photon scattering. Based on this formalism, we review applications to quantum control, including the design of state-to-state mappings, and quantum-state reconstruction via continuous weak measurement on a dynamically controlled ensemble.

Experimental measurement of preferences in health and healthcare using best-worst scaling: an overview.

PubMed

Mühlbacher, Axel C; Kaczynski, Anika; Zweifel, Peter; Johnson, F Reed

2016-12-01

Best-worst scaling (BWS), also known as maximum-difference scaling, is a multiattribute approach to measuring preferences. BWS aims at the analysis of preferences regarding a set of attributes, their levels or alternatives. It is a stated-preference method based on the assumption that respondents are capable of making judgments regarding the best and the worst (or the most and least important, respectively) out of three or more elements of a choice-set. As is true of discrete choice experiments (DCE) generally, BWS avoids the known weaknesses of rating and ranking scales while holding the promise of generating additional information by making respondents choose twice, namely the best as well as the worst criteria. A systematic literature review found 53 BWS applications in health and healthcare. This article expounds possibilities of application, the underlying theoretical concepts and the implementation of BWS in its three variants: 'object case', 'profile case', 'multiprofile case'. This paper contains a survey of BWS methods and revolves around study design, experimental design, and data analysis. Moreover the article discusses the strengths and weaknesses of the three types of BWS distinguished and offered an outlook. A companion paper focuses on special issues of theory and statistical inference confronting BWS in preference measurement.

Building and design defects observed in the residential sector and the types of damage observed in recent earthquakes in Turkey

NASA Astrophysics Data System (ADS)

Tolga Çöğürcü, M.

2015-01-01

Turkey is situated in a very active earthquake region. In the last century, several earthquakes resulted in thousands of deaths and enormous economic losses. In 1999, the Marmara earthquake had an approximate death toll of more than 20 000, and in 2011, the Van earthquake killed 604 people. In general, Turkish residential buildings have reinforced concrete structural systems. These reinforced concrete structures have several deficiencies, such as low concrete quality, non-seismic steel detailing, and inappropriate structural systems including several architectural irregularities. In this study, the general characteristics of Turkish building stock and the deficiencies observed in structural systems are explained, and illustrative figures are given with reference to Turkish Earthquake Code 2007 (TEC, 2007). The poor concrete quality, lack of lateral or transverse reinforcement in beam-column joints and column confinement zones, high stirrup spacings, under-reinforced columns and over-reinforced beams are the primary causes of failures. Other deficiencies include weak column-stronger beam formations, insufficient seismic joint separations, soft story or weak story irregularities and short columns. Similar construction and design mistakes are also observed in other countries situated on active earthquake belts. Existing buildings still have these undesirable characteristics, so to prepare for future earthquakes, they must be rehabilitated.

Construction and design defects in the residential buildings and observed earthquake damage types in Turkey

NASA Astrophysics Data System (ADS)

Cogurcu, M. T.

2015-04-01

Turkey is situated in a very active earthquake region. In the last century, several earthquakes resulted in thousands of deaths and enormous economic losses. In 1999, the Kocaeli earthquake had an approximate death toll of more than 20 000, and in 2011 the Van earthquake killed 604 people. In general, Turkish residential buildings have reinforced concrete structural systems. These reinforced concrete structures have several deficiencies, such as low concrete quality, non-seismic steel detailing and inappropriate structural systems including several architectural irregularities. In this study, the general characteristics of Turkish building stock and the deficiencies observed in structural systems are explained, and illustrative figures are given with reference to the Turkish Earthquake Code 2007. The poor concrete quality, lack of lateral or transverse reinforcement in beam-column joints and column confinement zones, high stirrup spacings, under-reinforced columns and over-reinforced beams are the primary causes of failures. Other deficiencies include weak-column-stronger-beam formations, insufficient seismic joint separations, soft-story or weak-story irregularities and short columns. Similar construction and design mistakes are also observed in other countries situated on active earthquake belts. Existing buildings still have these undesirable characteristics, and so to prepare for future earthquakes they must be rehabilitated.

Array design considerations for exploitation of stable weakly dispersive modal pulses in the deep ocean

NASA Astrophysics Data System (ADS)

Udovydchenkov, Ilya A.

2017-07-01

Modal pulses are broadband contributions to an acoustic wave field with fixed mode number. Stable weakly dispersive modal pulses (SWDMPs) are special modal pulses that are characterized by weak dispersion and weak scattering-induced broadening and are thus suitable for communications applications. This paper investigates, using numerical simulations, receiver array requirements for recovering information carried by SWDMPs under various signal-to-noise ratio conditions without performing channel equalization. Two groups of weakly dispersive modal pulses are common in typical mid-latitude deep ocean environments: the lowest order modes (typically modes 1-3 at 75 Hz), and intermediate order modes whose waveguide invariant is near-zero (often around mode 20 at 75 Hz). Information loss is quantified by the bit error rate (BER) of a recovered binary phase-coded signal. With fixed receiver depths, low BERs (less than 1%) are achieved at ranges up to 400 km with three hydrophones for mode 1 with 90% probability and with 34 hydrophones for mode 20 with 80% probability. With optimal receiver depths, depending on propagation range, only a few, sometimes only two, hydrophones are often sufficient for low BERs, even with intermediate mode numbers. Full modal resolution is unnecessary to achieve low BERs. Thus, a flexible receiver array of autonomous vehicles can outperform a cabled array.

Bridge pier foundation evaluation using cross-hole seismic tomographic imaging

NASA Astrophysics Data System (ADS)

Butchibabu, B.; Sandeep, N.; Sivaram, Y. V.; Jha, P. C.; Khan, P. K.

2017-09-01

An ambitious project connecting Jammu and Srinagar through a railway link in tectonically active and geologically complex Himalayan Mountain terrain is under progress. Under this project, the world's highest (359 m) railway arch-bridge is under construction across the River Chenab in the northern territory of India. This mega engineering structure has a two-fold ribbed arch design, comprising of steel girders. During the excavation for one of the concrete pillars on the right abutment, wide open joints and weak/shear zones were noticed. The width of these joints varies from 30 to 50 cm, trending along N170° with a dip of 65°. The foundation area of this pillar is 13 m × 24 m and on the cut slopes of the right bank of Chenab River. These exposed joints and weak zones were treated with consolidation grouting to strengthen the foundation area. To delineate the extent of these joints and weak zones below the foundation level, seismic tomography was carried out in five boreholes drilled for this purpose to cover the 300 sq-m area. The results of cross-hole seismic tomography reveals the presence of three low velocity (≤ 2600 m/s) anomalous zones below the foundation area. This also ascertained the efficacy of grouting in consolidating the joints and weak zones. Later, rock-mass quality (Q) was determined based on the relationship between the P-wave velocity and the Q-value (Barton, 2002) to infer the support system for the slope stabilization below the foundation. 3-D visualization of the seismic velocity demarcates the extent of weak or untreated zones. This methodology facilitates to update the design parameters according to Q-values during the construction stage and estimate the required level of reinforcement and support system. Similar methodology can be applicable in other areas under same site conditions.

Personalization and perceived personal relevance in computer-tailored persuasion in smoking cessation.

PubMed

Dijkstra, Arie; Ballast, Karien

2012-02-01

In most computer-tailored interventions, the recipient's name is used to personalize the information. This is done to increase the process of persuasion but few empirical data exist that support this notion. An experimental laboratory study was conducted to test the effects of mentioning the participants name and to study whether it was related to the depth of processing in a 2 (personalization/standard) × 2 (weak/strong arguments) design. Over 120 student smokers were randomly assigned to one of the four experimental conditions in which they read smoking cessation messages offering (pre-tested) strong or weak arguments. Personalization was applied by mentioning the recipient's first name three times in the text. The intention to quit smoking was the dependent variable. Personalization increased persuasion when perceived personal relevance was high, but it decreased persuasion when perceived personal relevance was low. The effects on persuasion were only present in the case of strong arguments. Personalization is not always effective, and it may even lead to less persuasion. Therefore, this often used way to tailor messages must be applied with care. ©2011 The British Psychological Society.

Fragment screening for drug leads by weak affinity chromatography (WAC-MS).

PubMed

Ohlson, Sten; Duong-Thi, Minh-Dao

2018-02-23

Fragment-based drug discovery is an important tool for design of small molecule hit-to-lead compounds against various biological targets. Several approved drugs have been derived from an initial fragment screen and many such candidates are in various stages of clinical trials. Finding fragment hits, that are suitable for optimisation by medicinal chemists, is still a challenge as the binding between the small fragment and its target is weak in the range of mM to µM of K d and irrelevant non-specific interactions are abundant in this area of transient interactions. Fortunately, there are methods that can study weak interactions quite efficiently of which NMR, surface plasmon resonance (SPR) and X-ray crystallography are the most prominent. Now, a new technology based on zonal affinity chromatography, weak affinity chromatography (WAC), has been introduced which has remedied many of the problems with other technologies. By combining WAC with mass spectrometry (WAC-MS), it is a powerful tool to identify binders quantitatively in terms of affinity and kinetics either from fragment libraries or from complex mixtures of biological extracts. As WAC-MS can be multiplexed by analysing mixtures of fragments (20-100 fragments) in one sample, this approach yields high throughput, where a whole library of e.g. >2000 fragments can be analysed quantitatively within a day. WAC-MS is easy to perform, where the robustness and quality of HPLC is fully utilized. This review will highlight the rationale behind the application of WAC-MS for fragment screening in drug discovery. Copyright © 2018 Elsevier Inc. All rights reserved.

Enhancing public involvement in assistive technology design research.

PubMed

Williamson, Tracey; Kenney, Laurence; Barker, Anthony T; Cooper, Glen; Good, Tim; Healey, Jamie; Heller, Ben; Howard, David; Matthews, Martin; Prenton, Sarah; Ryan, Julia; Smith, Christine

2015-05-01

To appraise the application of accepted good practice guidance on public involvement in assistive technology research and to identify its impact on the research team, the public, device and trial design. Critical reflection and within-project evaluation were undertaken in a case study of the development of a functional electrical stimulation device. Individual and group interviews were undertaken with lay members of a 10 strong study user advisory group and also research team members. Public involvement was seen positively by research team members, who reported a positive impact on device and study designs. The public identified positive impact on confidence, skills, self-esteem, enjoyment, contribution to improving the care of others and opportunities for further involvement in research. A negative impact concerned the challenge of engaging the public in dissemination after the study end. The public were able to impact significantly on the design of an assistive technology device which was made more fit for purpose. Research team attitudes to public involvement were more positive after having witnessed its potential first hand. Within-project evaluation underpins this case study which presents a much needed detailed account of public involvement in assistive technology design research to add to the existing weak evidence base. The evidence base for impact of public involvement in rehabilitation technology design is in need of development. Public involvement in co-design of rehabilitation devices can lead to technologies that are fit for purpose. Rehabilitation researchers need to consider the merits of active public involvement in research.

Shear Recovery Accuracy in Weak-Lensing Analysis with the Elliptical Gauss-Laguerre Method

NASA Astrophysics Data System (ADS)

Nakajima, Reiko; Bernstein, Gary

2007-04-01

We implement the elliptical Gauss-Laguerre (EGL) galaxy-shape measurement method proposed by Bernstein & Jarvis and quantify the shear recovery accuracy in weak-lensing analysis. This method uses a deconvolution fitting scheme to remove the effects of the point-spread function (PSF). The test simulates >107 noisy galaxy images convolved with anisotropic PSFs and attempts to recover an input shear. The tests are designed to be immune to statistical (random) distributions of shapes, selection biases, and crowding, in order to test more rigorously the effects of detection significance (signal-to-noise ratio [S/N]), PSF, and galaxy resolution. The systematic error in shear recovery is divided into two classes, calibration (multiplicative) and additive, with the latter arising from PSF anisotropy. At S/N > 50, the deconvolution method measures the galaxy shape and input shear to ~1% multiplicative accuracy and suppresses >99% of the PSF anisotropy. These systematic errors increase to ~4% for the worst conditions, with poorly resolved galaxies at S/N simeq 20. The EGL weak-lensing analysis has the best demonstrated accuracy to date, sufficient for the next generation of weak-lensing surveys.

Registered Nurses' Knowledge about Adverse Effects of Analgesics when Treating Postoperative Pain in Patients with Dementia.

PubMed

Rantala, Maija; Hartikainen, Sirpa; Kvist, Tarja; Kankkunen, Päivi

2015-08-01

Registered nurses (RNs) play a pivotal role in treating pain and preventing and recognizing the adverse effects (AEs) of analgesics in patients with dementia. The purpose of this study was to determine RNs' knowledge of potentially clinically relevant AEs of analgesics. A descriptive, cross-sectional study design was used. In all, 267 RNs treating orthopedic patients, including patients with dementia, in 7 university hospitals and 10 central hospitals in Finland, completed a questionnaire. Analgesics were defined according to the Anatomic Therapeutic Classification as strong opioids, weak opioids, nonsteroidal anti-inflammatory analgesics (NSAIDs), and paracetamol. Definitions of AEs were based on the literature. Logistic regression analysis was applied to analyze which variables predicted nurses' knowledge. The RNs had a clear understanding of the AEs of paracetamol and strong opioids. However, the AEs of NSAIDs, especially renal and cardiovascular AEs, were less well known. The median percentage of correct answers was 87% when asked about strong opioids, 73% for weak opioids, and 60% for NSAIDs. Younger RNs had better knowledge of opioid-related AEs (odds ratio [OR] per 1-year increase, 0.97; 95% confidence interval [CI], 0.94-1.00) and weak opioids (OR, 0.96; 95% CI, 0.93-0.99). This study provides evidence of a deficiency in RNs' knowledge, especially regarding the adverse renal and cardiovascular effects of NSAIDs. Such lack of knowledge indicates that hospitals may need to update the knowledge of older RNs, especially those who treat vulnerable patients with dementia. Copyright © 2015 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

Evidences on weaknesses and strengths from health financing after decentralization: lessons from Latin American countries.

PubMed

Arredondo, Armando; Orozco, Emanuel; De Icaza, Esteban

2005-01-01

The main objective was to identify trends and evidence on health financing after health care decentralization. Evaluative research with a before-after design integrating qualitative and quantitative analysis. Taking into account feasibility, political and technical criteria, three Latin American countries were selected as study populations: Mexico, Nicaragua and Peru. The methodology had two main phases. In the first phase, the study referred to secondary sources of data and documents to obtain information about the following variables: type of decentralization implemented, source of finance, funds of financing, providers, final use of resources and mechanisms for resource allocation. In the second phase, the study referred to primary data collected in a survey of key personnel from the health sectors of each country. The trends and evidence reported in all five financing indicators may identify major weaknesses and strengths in health financing. Weaknesses: a lack of human resources trained in health economics who can implement changes, a lack of financial resource independence between the local and central levels, the negative behavior of the main macro-economic variables, and the difficulty in developing new financing alternatives. Strengths: the sharing between the central level and local levels of responsibility for financing health services, the implementation of new organizational structures for the follow-up of financial changes at the local level, the development and implementation of new financial allocation mechanisms taking as a basis the efficiency and equity principles, new technique of a per-capita adjustment factor corrected at the local health needs, and the increase of financing contributions from households and local levels of government.

Understanding Youth Antisocial Behavior Using Neuroscience through a Developmental Psychopathology Lens: Review, Integration, and Directions for Research

PubMed Central

Hyde, Luke W.; Shaw, Daniel S.; Hariri, Ahmad R.

2013-01-01

Youth antisocial behavior (AB) is an important public health concern impacting perpetrators, victims, and society. Functional neuroimaging is becoming a more common and useful modality for understanding neural correlates of youth AB. Although there has been a recent increase in neuroimaging studies of youth AB and corresponding theoretical articles on the neurobiology of AB, there has been little work critically examining the strengths and weaknesses of individual studies and using this knowledge to inform the design of future studies. Additionally, research on neuroimaging and youth AB has not been integrated within the broader framework of developmental psychopathology. Thus, this paper provides an in-depth review of the youth AB functional neuroimaging literature with the following goals: 1. to evaluate how this literature has informed our understanding of youth AB, 2. to evaluate current neuroimaging studies of youth AB from a developmental psychopathology perspective with a focus on integrating research from neuroscience and developmental psychopathology, as well as placing this research in the context of other related areas (e.g., psychopathy, molecular genetics), and 3. to examine strengths and weaknesses of neuroimaging and behavioral studies of youth AB to suggest how future studies can develop a more informed and integrated understanding of youth AB. PMID:24273368

The expert site visitor chairperson: supportive, effective, efficient.

PubMed

Wawrzynski, Mary; Davidhizar, Ruth

2004-01-01

In much of nursing academe the words "self-study" and "accreditation site visit" are enough to squeeze the coronary arteries of nurse administrators and faculty. Such words conjure up images of months of labor intensive work, anxiety and concerns that all might not go well and that the program's accreditation will be placed in jeopardy. Both the completion of a self-study, designed as a self-assessment of program strengths and weaknesses, and preparation for the on-site visit are an addition to the normal tasks of nurse administrators and thus often result in overtaxing resources allotted to maintenance of the program.

[Methodological problems in the scientific research on HIV /AIDS in Bolivia].

PubMed

Hita, Susana Ramírez

2013-05-01

This paper discusses the methodological problems in the scientific research on HIV/AIDS in Bolivia, both in the areas of epidemiology and social sciences. Studies associated with this research served as the basis for the implementation of health programs run by The Global Fund, The Pan-American Health Organization, International Cooperation, Non-Governmental Organizations and the Bolivian Ministry of Health and Sports. An analysis of the methodological contradictions and weaknesses was made by reviewing the bibliography of the studies and by conducting qualitative methodological research, that was focused on the quality of health care available to people living with HIV/AIDS in public hospitals and health centers, and looked at how programs targeted at this sector of the population are designed and delivered. In this manner, it was possible to observe the shortcomings of the methodological design in the epidemiological and social science studies which serve as the basis for the implementation of these health programs.

Prostate cancer link to vasectomy is weak.

PubMed

1998-03-01

Health care providers and men seeking vasectomies are still unsure about the nature of the association between vasectomy and prostate cancer. Two large cohort studies published in 1993 found increased relative risks for prostate cancer in vasectomized men of 1.56 and 1.66. However, this level of increased relative risk represents only a weak association between the procedure and cancer. Three other studies of similar design reported no such association. Several divisions of the National Institutes of Health examined the research and issued the joint statement in 1993 that providers should continue to offer vasectomy and perform the procedure, the reversal of vasectomies is unwarranted to prevent prostate cancer, and screening for prostate cancer should not be any different for men who have had a vasectomy than for those who have not. Joel Feigin, MD, associate professor of family medicine at Robert Wood Johnson Medical School in New Brunswick, NJ, and director of the Coventry No-Scalpel Vasectomy Center in Phillipsburg, NJ, recommends dealing proactively with the cancer link as a standard part of counseling. Thomas R. Pritchett, MD, a urologist on the clinical faculty of the University of Washington and the department of urology at Virginia Mason Medical Center in Seattle says that the strongest link to increased risk for prostate cancer is family history. Diet, race, and vasectomy are only weak associations. A definite link also exists between testosterone and prostate cancer, but undergoing vasectomy neither increases nor decreases a man's testosterone level.

Analysis of Teacher Beliefs and Efficacy for Teaching Writing to Weak Learners

ERIC Educational Resources Information Center

Mohar, Tunku Mohani Tunku; Singh, Charajit Kaur Swaran; Kepol, Napisah; Ahmad, Ahmad Zainuri Loap; Moneyam, Sasigaran

2017-01-01

The present study investigated the beliefs and efficacy of a teacher teaching English to students who were weak at the language. The objective of the study was mainly to investigate the beliefs and efficacy of the ESL teacher for teaching writing to weak learners. The research was a case study of the English Language teacher teaching Form Three…

Fatigue is associated with muscle weakness in Ehlers-Danlos syndrome: an explorative study.

PubMed

Voermans, N C; Knoop, H; Bleijenberg, G; van Engelen, B G

2011-06-01

Ehlers-Danlos syndrome (EDS) is a clinically and genetically heterogeneous group of inherited connective tissue disorders characterised by joint hypermobility, skin hyperextensibility and tissue fragility. It has recently been shown that muscle weakness occurs frequently in EDS, and that fatigue is a common and clinically important symptom. The aim of this study was to investigate the relationship between fatigue severity and subjective and objective measures of muscle weakness. Furthermore, the predictive value of muscle weakness for fatigue severity was determined, together with that of pain and physical activity. An explorative, cross-sectional, observational study. Thirty EDS patients, recruited from the Dutch patient association, were investigated at the neuromuscular outpatient department of a tertiary referral centre in The Netherlands. Muscle strength measured with manual muscle strength testing and hand-held dynamometry. Self-reported muscle weakness, pain, physical activity levels and fatigue were assessed with standardised questionnaires. Fatigue severity in EDS was significantly correlated with measured and self-reported muscle weakness (r=-0.408 for manual muscle strength, r=0.461 for hand-held dynamometry and r=0.603 for self-reported muscle weakness). Both muscle weakness and pain severity were significant predictors of fatigue severity in a multiple regression analysis. The results suggest a positive and direct relationship between fatigue severity and muscle weakness in EDS. Future research should focus on the relationship between fatigue, muscle weakness and objectively measured physical activity, preferably in a larger cohort of EDS patients. Copyright © 2010 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Rooftop hospital gardens for physical therapy: a post-occupancy evaluation.

PubMed

Davis, Brad E

2011-01-01

The goal of this study was to understand successes and weaknesses of a rooftop hospital garden used primarily for physical therapy. Literature on the healing benefits of nature and designed outdoor spaces in healthcare contexts continues to become more focused on specific patient populations. This study contributes to the knowledge of rooftop hospital gardens and gardens for physical rehabilitation. A post-occupancy evaluation was conducted using interviews with a lead therapist and landscape architect, behavior mapping, a staff survey, and a patient questionnaire. The designer and administrative staff perceived high accessibility while patients and staff reported low accessibility. Patients reported high satisfaction with the garden while staff reported little time for garden use. Poor maintenance decisions resulted in decreased functional and aesthetic value. Garden elements take on added layers of meaning and value to users seeking to escape the indoor environment, placing increased importance on evidence-based site design. Multiple perspectives must be considered in facility and garden master planning. Finally, designers and horticultural therapists must be retained in garden management to preserve and enhance garden functionality.

Evaluation of designed ligands by a multiple screening method: Application to glycogen phosphorylase inhibitors constructed with a variety of approaches

NASA Astrophysics Data System (ADS)

So, Sung-Sau; Karplus, Martin

2001-07-01

Glycogen phosphorylase (GP) is an important enzyme that regulates blood glucose level and a key therapeutic target for the treatment of type II diabetes. In this study, a number of potential GP inhibitors are designed with a variety of computational approaches. They include the applications of MCSS, LUDI and CoMFA to identify additional fragments that can be attached to existing lead molecules; the use of 2D and 3D similarity-based QSAR models (HQSAR and SMGNN) and of the LUDI program to identify novel molecules that may bind to the glucose binding site. The designed ligands are evaluated by a multiple screening method, which is a combination of commercial and in-house ligand-receptor binding affinity prediction programs used in a previous study (So and Karplus, J. Comp.-Aid. Mol. Des., 13 (1999), 243-258). Each method is used at an appropriate point in the screening, as determined by both the accuracy of the calculations and the computational cost. A comparison of the strengths and weaknesses of the ligand design approaches is made.

A synthetic biological quantum optical system

DOE PAGES

Lishchuk, Anna; Kodali, Goutham; Mancini, Joshua A.; ...

2018-01-01

Strong coupling between plasmon modes and chlorins in synthetic light-harvesting maquette proteins yields hybrid light–matter states (plexcitons) whose energies are controlled by design of protein structure, enabling the creation of new states not seen under weak coupling.

Design of an Internal Model Control strategy for single-phase grid-connected PWM inverters and its performance analysis with a non-linear local load and weak grid.

PubMed

Chaves, Eric N; Coelho, Ernane A A; Carvalho, Henrique T M; Freitas, Luiz C G; Júnior, João B V; Freitas, Luiz C

2016-09-01

This paper presents the design of a controller based on Internal Model Control (IMC) applied to a grid-connected single-phase PWM inverter. The mathematical modeling of the inverter and the LCL output filter, used to project the 1-DOF IMC controller, is presented and the decoupling of grid voltage by a Feedforward strategy is analyzed. A Proportional - Resonant Controller (P+Res) was used for the control of the same plant in the running of experimental results, thus moving towards the discussion of differences regarding IMC and P+Res performances, which arrived at the evaluation of the proposed control strategy. The results are presented for typical conditions, for weak-grid and for non-linear local load, in order to verify the behavior of the controller against such situations. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

Fault recovery characteristics of the fault tolerant multi-processor

NASA Technical Reports Server (NTRS)

Padilla, Peter A.

1990-01-01

The fault handling performance of the fault tolerant multiprocessor (FTMP) was investigated. Fault handling errors detected during fault injection experiments were characterized. In these fault injection experiments, the FTMP disabled a working unit instead of the faulted unit once every 500 faults, on the average. System design weaknesses allow active faults to exercise a part of the fault management software that handles byzantine or lying faults. It is pointed out that these weak areas in the FTMP's design increase the probability that, for any hardware fault, a good LRU (line replaceable unit) is mistakenly disabled by the fault management software. It is concluded that fault injection can help detect and analyze the behavior of a system in the ultra-reliable regime. Although fault injection testing cannot be exhaustive, it has been demonstrated that it provides a unique capability to unmask problems and to characterize the behavior of a fault-tolerant system.

Principles and Design of a Zeeman–Sisyphus Decelerator for Molecular Beams

PubMed Central

Tarbutt, M. R.

2016-01-01

Abstract We explore a technique for decelerating molecules using a static magnetic field and optical pumping. Molecules travel through a spatially varying magnetic field and are repeatedly pumped into a weak‐field seeking state as they move towards each strong field region, and into a strong‐field seeking state as they move towards weak field. The method is time‐independent and so is suitable for decelerating both pulsed and continuous molecular beams. By using guiding magnets at each weak field region, the beam can be simultaneously guided and decelerated. By tapering the magnetic field strength in the strong field regions, and exploiting the Doppler shift, the velocity distribution can be compressed during deceleration. We develop the principles of this deceleration technique, provide a realistic design, use numerical simulations to evaluate its performance for a beam of CaF, and compare this performance to other deceleration methods. PMID:27629547

Optics ellipticity performance of an unobscured off-axis space telescope.

PubMed

Zeng, Fei; Zhang, Xin; Zhang, Jianping; Shi, Guangwei; Wu, Hongbo

2014-10-20

With the development of astronomy, more and more attention is paid to the survey of dark matter. Dark matter cannot be seen directly but can be detected by weak gravitational lensing measurement. Ellipticity is an important parameter used to define the shape of a galaxy. Galaxy ellipticity changes with weak gravitational lensing and nonideal optics. With our design of an unobscured off-axis telescope, we implement the simulation and calculation of optics ellipticity. With an accurate model of optics PSF, the characteristic of ellipticity is modeled and analyzed. It is shown that with good optical design, the full field ellipticity can be quite small. The spatial ellipticity change can be modeled by cubic interpolation with very high accuracy. We also modeled the ellipticity variance with time and analyzed the tolerance. It is shown that the unobscured off-axis telescope has good ellipticity performance and fulfills the requirement of dark matter survey.

Navigator GPS Receiver for Fast Acquisition and Weak Signal Space Applications

NASA Technical Reports Server (NTRS)

Winternitz, Luke; Moreau, Michael; Boegner, Gregory J.; Sirotzky, Steve

2004-01-01

NASA Goddard Space Flight Center (GSFC) is developing a new space-borne GPS receiver that can operate effectively in the full range of Earth orbiting missions from Low Earth Orbit (LEO) to geostationary and beyond. Navigator is designed to be a fully space flight qualified GPS receiver optimized for fast signal acquisition and weak signal tracking. The fast acquisition capabilities provide exceptional time to first fix performance (TIFF) with no a priori receiver state or GPS almanac information, even in the presence of high Doppler shifts present in LEO (or near perigee in highly eccentric orbits). The fast acquisition capability also makes it feasible to implement extended correlation intervals and therefore significantly reduce Navigator s acquisition threshold. This greatly improves GPS observability when the receiver is above the GPS constellation (and satellites must be tracked from the opposite side of the Earth) by providing at least 10 dB of increased acquisition sensitivity. Fast acquisition and weak signal tracking algorithms have been implemented and validated on a hardware development board. A fully functional version of the receiver, employing most of the flight parts, with integrated navigation software is expected by mid 2005. An ultimate goal of this project is to license the Navigator design to an industry partner who will then market the receiver as a commercial product.

A Carrier Estimation Method Based on MLE and KF for Weak GNSS Signals.

PubMed

Zhang, Hongyang; Xu, Luping; Yan, Bo; Zhang, Hua; Luo, Liyan

2017-06-22

Maximum likelihood estimation (MLE) has been researched for some acquisition and tracking applications of global navigation satellite system (GNSS) receivers and shows high performance. However, all current methods are derived and operated based on the sampling data, which results in a large computation burden. This paper proposes a low-complexity MLE carrier tracking loop for weak GNSS signals which processes the coherent integration results instead of the sampling data. First, the cost function of the MLE of signal parameters such as signal amplitude, carrier phase, and Doppler frequency are used to derive a MLE discriminator function. The optimal value of the cost function is searched by an efficient Levenberg-Marquardt (LM) method iteratively. Its performance including Cramér-Rao bound (CRB), dynamic characteristics and computation burden are analyzed by numerical techniques. Second, an adaptive Kalman filter is designed for the MLE discriminator to obtain smooth estimates of carrier phase and frequency. The performance of the proposed loop, in terms of sensitivity, accuracy and bit error rate, is compared with conventional methods by Monte Carlo (MC) simulations both in pedestrian-level and vehicle-level dynamic circumstances. Finally, an optimal loop which combines the proposed method and conventional method is designed to achieve the optimal performance both in weak and strong signal circumstances.

Phthalates and other additives in plastics: human exposure and associated health outcomes

PubMed Central

Meeker, John D.; Sathyanarayana, Sheela; Swan, Shanna H.

2009-01-01

Concern exists over whether additives in plastics to which most people are exposed, such as phthalates, bisphenol A or polybrominated diphenyl ethers, may cause harm to human health by altering endocrine function or through other biological mechanisms. Human data are limited compared with the large body of experimental evidence documenting reproductive or developmental toxicity in relation to these compounds. Here, we discuss the current state of human evidence, as well as future research trends and needs. Because exposure assessment is often a major weakness in epidemiological studies, and in utero exposures to reproductive or developmental toxicants are important, we also provide original data on maternal exposure to phthalates during and after pregnancy (n = 242). Phthalate metabolite concentrations in urine showed weak correlations between pre- and post-natal samples, though the strength of the relationship increased when duration between the two samples decreased. Phthalate metabolite levels also tended to be higher in post-natal samples. In conclusion, there is a great need for more human studies of adverse health effects associated with plastic additives. Recent advances in the measurement of exposure biomarkers hold much promise in improving the epidemiological data, but their utility must be understood to facilitate appropriate study design. PMID:19528058

Effects of protein or amino-acid supplementation on the physical growth of young children in low-income countries

PubMed Central

Arsenault, Joanne E; Brown, Kenneth H

2017-01-01

Abstract Child growth stunting is common in low-income countries, possibly due to insufficient protein intakes. Most previous studies have concluded that children’s protein intakes are adequate in relation to estimated requirements, but these studies did not consider issues of protein digestibility and effects of infection on dietary protein utilization. Using an alternative approach to assess the possible role of protein inadequacy in children’s growth restriction, the results of 18 intervention trials in which supplementary protein or amino acids were provided to children ages 6–35 months and growth outcomes were reviewed. Eight studies conducted in hospitalized children recovering from acute malnutrition found that the recommended protein intake levels for healthy children supported normal growth rates, but higher intakes were needed for accelerated rates of “catch-up” growth. Ten community-based studies did not demonstrate a consistent benefit of supplemental protein on children’s growth. However, weaknesses in the study designs limit the conclusions that can be drawn from these studies, and additional appropriately designed trials are needed to answer this question definitively. Recommendations for optimizing future study designs are provided herein. PMID:28938793

[Successful aging and indicators of frailty in the elderly. Octabaix Study].

PubMed

Ferrer, Assumpta; Formiga, Francesc; Sanz, Héctor; Monserrate, Elena; Verges, Dolors

2014-11-01

Successful aging as a process of adaptation to the optimal state is little known in older people. To describe successful aging and to analyze the factors associated with frailty in people aged 86 years. A cross-sectional study of a clinical trial at the second year of follow-up (Octabaix Study). Seven Primary Care Centers. Non-institutionalized subjects born in 1924. Data on sociodemographic, comorbidity and geriatric assessment scales were collected. Frailty was defined by the presence of 3 or more of the following criteria: muscle weakness, slow walking, weight loss, exhaustion, low physical activity. Successful aging was defined as: Barthel index >90/100 and Lobo test ≥ 24/35. Multiple regression analysis was performed. A total of 273 patients were evaluated, 39.2% men. The prevalence of successful aging was 47.2% (129). In the unsuccessful aging, the frailty prevalence was 34.7% (50). The frailty factors associated with unsuccessful aging were low activity (OR: 7.56; 95%CI: 3.8 -14.9), weakness (OR: 6.08; 95%CI: 2.5-14.7), slowness (OR: 5.1; 95%CI: 2.8-9.5), and exhaustion (OR: 3.6; 95%CI: 1.6-8.3). The prevalence of successful aging is high in 86-year-old community-dwelling subjects. The low physical activity multiplied by seven, and muscle weakness by 6, were the factors most associated with unsuccessful aging. Therefore, incorporating screening designed to detect these two factors could improve future interventions towards more optimal aging in the community, if these results are confirmed in future studies. Copyright © 2013 Elsevier España, S.L.U. All rights reserved.

A Design Method for Topologically Insulating Metamaterials

NASA Astrophysics Data System (ADS)

Matlack, Kathryn; Serra-Garcia, Marc; Palermo, Antonio; Huber, Sebastian; Daraio, Chiara

Topological insulators are a unique class of electronic materials that exhibit protected edge states that are insulating in the bulk, and immune to back-scattering and defects. Discrete models, such as mass-spring systems, provide a means to translate these properties, based on the quantum hall spin effect, to the mechanical domain. This talk will present how to engineer a 2D mechanical metamaterial that supports topologically-protected and defect-immune edge states, directly from the mass-spring model of a topological insulator. The design method uses combinatorial searches plus gradient-based optimizations to determine the configuration of the metamaterials building blocks that leads to the global behavior specified by the target mass-spring model. We use metamaterials with weakly coupled unit cells to isolate the dynamics within our frequency range of interest and to enable a systematic design process. This approach can generally be applied to implement behaviors of a discrete model directly in mechanical, acoustic, or photonic metamaterials within the weak-coupling regime. This work was partially supported by the ETH Postdoctoral Fellowship, and by the Swiss National Science Foundation.

Constructibility Challenges for Perimeter Control Blasting and Slope Development in Shale and Other "Weak" Rocks

NASA Astrophysics Data System (ADS)

Scarpato, D. J.

2016-02-01

Slope construction in shale can present some interesting challenges for geotechnical design engineers and contractors alike. There are challenges that can be expected and designed for; however, all too frequently, such challenges manifest themselves as "surprises" in the field. Common constructibility challenges can include drill hole deviation during drilling for controlled blasting; and, excavation slope instability arising from inconsistent perimeter control drilling. Drill hole deviation results from the cumulative effects from both drilling mechanics and rock mass conditions. Once a hole has initiated the deviation trajectory, it is difficult to rectify drill steel position. Although such challenges are not necessarily unique to shale, they are often exacerbated by weak, weathered and transversely isotropic nature of bedrock conditions. All too often, the working assumption is that shale is "soft" and easily excavatable; however, this blanket assumption can prove to be costly. This paper is intended to provide design professionals and contractors with the practical considerations needed to avoid the "surprises" associated with drill hole deviation, and minimize the potential for costly claims.

Program factors related to women's substance abuse treatment retention and other outcomes: a review and critique.

PubMed

Sun, An-Pyng

2006-01-01

This study examined program factors related to women's substance abuse treatment outcomes. Although substance abuse research is traditionally focused on men, some more recent studies target women. A systematic review of 35 empirical studies that included solely women subjects or that analyzed female subjects separately from male subjects revealed five elements related to women's substance abuse treatment effectiveness; these are (1) single- versus mixed-sex programs, (2) treatment intensity, (3) provision for child care, (4) case management and the "one-stop shopping" model, and (5) supportive staff plus the offering of individual counseling. Although all 35 studies contribute to the knowledge base, critiques of six areas of design weakness in the studies were included to provide directions for future studies; these are (1) lack of a randomized controlled design, (2) nondisentanglement of multiple conditions, (3) lack of a consistent definition for treatment factors and outcomes, (4) small sample size, (5) lack of thorough program description, and (6) lack of thorough statistical analyses.

Finite element formulation with embedded weak discontinuities for strain localization under dynamic conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jin, Tao; Mourad, Hashem M.; Bronkhorst, Curt A.

Here, we present an explicit finite element formulation designed for the treatment of strain localization under highly dynamic conditions. We also used a material stability analysis to detect the onset of localization behavior. Finite elements with embedded weak discontinuities are employed with the aim of representing subsequent localized deformation accurately. The formulation and its algorithmic implementation are described in detail. Numerical results are presented to illustrate the usefulness of this computational framework in the treatment of strain localization under highly dynamic conditions, and to examine its performance characteristics in the context of two-dimensional plane-strain problems.

Finite element formulation with embedded weak discontinuities for strain localization under dynamic conditions

DOE PAGES

Jin, Tao; Mourad, Hashem M.; Bronkhorst, Curt A.; ...

2017-09-13

Here, we present an explicit finite element formulation designed for the treatment of strain localization under highly dynamic conditions. We also used a material stability analysis to detect the onset of localization behavior. Finite elements with embedded weak discontinuities are employed with the aim of representing subsequent localized deformation accurately. The formulation and its algorithmic implementation are described in detail. Numerical results are presented to illustrate the usefulness of this computational framework in the treatment of strain localization under highly dynamic conditions, and to examine its performance characteristics in the context of two-dimensional plane-strain problems.

Study of weak solutions for parabolic variational inequalities with nonstandard growth conditions.

PubMed

Dong, Yan

2018-01-01

In this paper, we study the degenerate parabolic variational inequality problem in a bounded domain. First, the weak solutions of the variational inequality are defined. Second, the existence and uniqueness of the solutions in the weak sense are proved by using the penalty method and the reduction method.

Closing the design loop on HiMAT (highly maneuverable aircraft technology)

NASA Technical Reports Server (NTRS)

Putnam, T. W.; Robinson, M. R.

1984-01-01

The design methodology used in the HiMAT program and the wind tunnel development activities are discussed. Selected results from the flight test program are presented and the strengths and weaknesses of testing advanced technology vehicles using the RPV concept is examined. The role of simulation on the development of digital flight control systems and in RPV's in particular is emphasized.

Test Review: Wiig, E H., Semel, E., Secord, W. A. (2013) Clinical Evaluation of Language Fundamentals-Fifth Edition (CELF-5). Bloomington, MN: NCS Pearson

ERIC Educational Resources Information Center

Coret, Marian C.; McCrimmon, Adam W.

2015-01-01

The "Clinical Evaluation of Language Fundamentals-Fifth Edition" (CELF-5; Wiig, Semel, & Secord, 2013) is a recently updated battery of tests designed to assess, diagnose, and measure changes in language and communication in individuals 5 to 21 years of age. Designed to identify language strengths and weaknesses, determine service…

Exercise of the SSM/PMAD Breadboard. [Space Station Module/Power Management And Distribution

NASA Technical Reports Server (NTRS)

Walls, Bryan

1989-01-01

The Space Station Module Power Management and Distribution (SSM/PMAD) Breadboard is a test facility designed for advanced development of space power automation. Originally designed for 20-kHz power, the system is being converted to work with direct current (dc). Power levels are on a par with those expected for a Space Station module. Some of the strengths and weaknesses of the SSM/PMAD system in design and function are examined, and the future directions foreseen for the system are outlined.

A Simulation Study of Threats to Validity in Quasi-Experimental Designs: Interrelationship between Design, Measurement, and Analysis.

PubMed

Holgado-Tello, Fco P; Chacón-Moscoso, Salvador; Sanduvete-Chaves, Susana; Pérez-Gil, José A

2016-01-01

The Campbellian tradition provides a conceptual framework to assess threats to validity. On the other hand, different models of causal analysis have been developed to control estimation biases in different research designs. However, the link between design features, measurement issues, and concrete impact estimation analyses is weak. In order to provide an empirical solution to this problem, we use Structural Equation Modeling (SEM) as a first approximation to operationalize the analytical implications of threats to validity in quasi-experimental designs. Based on the analogies established between the Classical Test Theory (CTT) and causal analysis, we describe an empirical study based on SEM in which range restriction and statistical power have been simulated in two different models: (1) A multistate model in the control condition (pre-test); and (2) A single-trait-multistate model in the control condition (post-test), adding a new mediator latent exogenous (independent) variable that represents a threat to validity. Results show, empirically, how the differences between both the models could be partially or totally attributed to these threats. Therefore, SEM provides a useful tool to analyze the influence of potential threats to validity.

A Simulation Study of Threats to Validity in Quasi-Experimental Designs: Interrelationship between Design, Measurement, and Analysis

PubMed Central

Holgado-Tello, Fco. P.; Chacón-Moscoso, Salvador; Sanduvete-Chaves, Susana; Pérez-Gil, José A.

2016-01-01

The Campbellian tradition provides a conceptual framework to assess threats to validity. On the other hand, different models of causal analysis have been developed to control estimation biases in different research designs. However, the link between design features, measurement issues, and concrete impact estimation analyses is weak. In order to provide an empirical solution to this problem, we use Structural Equation Modeling (SEM) as a first approximation to operationalize the analytical implications of threats to validity in quasi-experimental designs. Based on the analogies established between the Classical Test Theory (CTT) and causal analysis, we describe an empirical study based on SEM in which range restriction and statistical power have been simulated in two different models: (1) A multistate model in the control condition (pre-test); and (2) A single-trait-multistate model in the control condition (post-test), adding a new mediator latent exogenous (independent) variable that represents a threat to validity. Results show, empirically, how the differences between both the models could be partially or totally attributed to these threats. Therefore, SEM provides a useful tool to analyze the influence of potential threats to validity. PMID:27378991

Protocol for diaphragm pacing in patients with respiratory muscle weakness due to motor neurone disease (DiPALS): a randomised controlled trial

PubMed Central

2012-01-01

Background Motor neurone disease (MND) is a devastating illness which leads to muscle weakness and death, usually within 2-3 years of symptom onset. Respiratory insufficiency is a common cause of morbidity, particularly in later stages of MND and respiratory complications are the leading cause of mortality in MND patients. Non Invasive Ventilation (NIV) is the current standard therapy to manage respiratory insufficiency. Some MND patients however do not tolerate NIV due to a number of issues including mask interface problems and claustrophobia. In those that do tolerate NIV, eventually respiratory muscle weakness will progress to a point at which intermittent/overnight NIV is ineffective. The NeuRx RA/4 Diaphragm Pacing System was originally developed for patients with respiratory insufficiency and diaphragm paralysis secondary to stable high spinal cord injuries. The DiPALS study will assess the effect of diaphragm pacing (DP) when used to treat patients with MND and respiratory insufficiency. Method/Design 108 patients will be recruited to the study at 5 sites in the UK. Patients will be randomised to either receive NIV (current standard care) or receive DP in addition to NIV. Study participants will be required to complete outcome measures at 5 follow up time points (2, 3, 6, 9 and 12 months) plus an additional surgery and 1 week post operative visit for those in the DP group. 12 patients (and their carers) from the DP group will also be asked to complete 2 qualitative interviews. Discussion The primary objective of this trial will be to evaluate the effect of Diaphragm Pacing (DP) on survival over the study duration in patients with MND with respiratory muscle weakness. The project is funded by the National Institute for Health Research, Health Technology Assessment (HTA) Programme (project number 09/55/33) and the Motor Neurone Disease Association and the Henry Smith Charity. Trial Registration: Current controlled trials ISRCTN53817913. The views and opinions expressed therein are those of the authors and do not necessarily reflect those of the HTA programme, NIHR, NHS or the Department of Health. PMID:22897892

Cultivating cohort studies for observational translational research.

PubMed

Ransohoff, David F

2013-04-01

"Discovery" research about molecular markers for diagnosis, prognosis, or prediction of response to therapy has frequently produced results that were not reproducible in subsequent studies. What are the reasons, and can observational cohorts be cultivated to provide strong and reliable answers to those questions? Experimental Selected examples are used to illustrate: (i) what features of research design provide strength and reliability in observational studies about markers of diagnosis, prognosis, and response to therapy? (ii) How can those design features be cultivated in existing observational cohorts, for example, within randomized controlled clinical trial (RCT), other existing observational research studies, or practice settings like health maintenance organization (HMOs)? Examples include a study of RNA expression profiles of tumor tissue to predict prognosis of breast cancer, a study of serum proteomics profiles to diagnose ovarian cancer, and a study of stool-based DNA assays to screen for colon cancer. Strengths and weaknesses of observational study design features are discussed, along with lessons about how features that help assure strength might be "cultivated" in the future. By considering these examples and others, it may be possible to develop a process of "cultivating cohorts" in ongoing RCTs, observational cohort studies, and practice settings like HMOs that have strong features of study design. Such an effort could produce sources of data and specimens to reliably answer questions about the use of molecular markers in diagnosis, prognosis, and response to therapy.

Comparison of two gas chromatograph models and analysis of binary data

NASA Technical Reports Server (NTRS)

Keba, P. S.; Woodrow, P. T.

1972-01-01

The overall objective of the gas chromatograph system studies is to generate fundamental design criteria and techniques to be used in the optimum design of the system. The particular tasks currently being undertaken are the comparison of two mathematical models of the chromatograph and the analysis of binary system data. The predictions of two mathematical models, an equilibrium absorption model and a non-equilibrium absorption model exhibit the same weaknesses in their inability to predict chromatogram spreading for certain systems. The analysis of binary data using the equilibrium absorption model confirms that, for the systems considered, superposition of predicted single component behaviors is a first order representation of actual binary data. Composition effects produce non-idealities which limit the rigorous validity of superposition.

Weak-light Phase-locking for LISA

NASA Technical Reports Server (NTRS)

McNamara, Paul W.

2004-01-01

The long armlengths of the LISA interferometer, and the finite aperture of the telescope, leads to an optical power attenuation of approximately equal to 10(exp -10) of the transmitted to received light. Simple reflection at the end of the arm is therefore not an optimum interferometric design. Instead, a local laser is offset phase-locked to the weak incoming beam, transferring the phase information of the incoming to the outgoing light. This paper reports on an experiment to characterize a weak light phase-locking scheme suitable for LISA in which a diode-pumped, Nd:YAG, non-planar ring oscillator (NPRO) is offset phase-locked to a low power (13pW) frequency stabilised master NPRO. Preliminary results of the relative phase noise of the slave laser shows shot noise limited performance above 0.4 Hz. Excess noise is observed at lower frequencies, most probably due to thermal effects in the optical arrangement and phase sensing electronics.

Quantitative Universality for a Class of Weakly Chaotic Systems

NASA Astrophysics Data System (ADS)

Venegeroles, Roberto

2014-02-01

We consider a general class of intermittent maps designed to be weakly chaotic, i.e., for which the separation of trajectories of nearby initial conditions is weaker than exponential. We show that all its spatio and temporal properties, hitherto regarded independently in the literature, can be represented by a single characteristic function ϕ. A universal criterion for the choice of ϕ is obtained within the Feigenbaum's renormalization-group approach. We find a general expression for the dispersion rate ζ( t) of initially nearby trajectories and we show that the instability scenario for weakly chaotic systems is more general than that originally proposed by Gaspard and Wang (Proc. Natl. Acad. Sci. USA 85:4591, 1988). We also consider a spatially extended version of such class of maps, which leads to anomalous diffusion, and we show that the mean squared displacement satisfies σ 2( t)˜ ζ( t). To illustrate our results, some examples are discussed in detail.

A hybridized formulation for the weak Galerkin mixed finite element method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mu, Lin; Wang, Junping; Ye, Xiu

This paper presents a hybridized formulation for the weak Galerkin mixed finite element method (WG-MFEM) which was introduced and analyzed in Wang and Ye (2014) for second order elliptic equations. The WG-MFEM method was designed by using discontinuous piecewise polynomials on finite element partitions consisting of polygonal or polyhedral elements of arbitrary shape. The key to WG-MFEM is the use of a discrete weak divergence operator which is defined and computed by solving inexpensive problems locally on each element. The hybridized formulation of this paper leads to a significantly reduced system of linear equations involving only the unknowns arising frommore » the Lagrange multiplier in hybridization. Optimal-order error estimates are derived for the hybridized WG-MFEM approximations. In conclusion, some numerical results are reported to confirm the theory and a superconvergence for the Lagrange multiplier.« less

A hybridized formulation for the weak Galerkin mixed finite element method

DOE PAGES

Mu, Lin; Wang, Junping; Ye, Xiu

2016-01-14

This paper presents a hybridized formulation for the weak Galerkin mixed finite element method (WG-MFEM) which was introduced and analyzed in Wang and Ye (2014) for second order elliptic equations. The WG-MFEM method was designed by using discontinuous piecewise polynomials on finite element partitions consisting of polygonal or polyhedral elements of arbitrary shape. The key to WG-MFEM is the use of a discrete weak divergence operator which is defined and computed by solving inexpensive problems locally on each element. The hybridized formulation of this paper leads to a significantly reduced system of linear equations involving only the unknowns arising frommore » the Lagrange multiplier in hybridization. Optimal-order error estimates are derived for the hybridized WG-MFEM approximations. In conclusion, some numerical results are reported to confirm the theory and a superconvergence for the Lagrange multiplier.« less

Using Laboratory Homework to Facilitate Skill Integration and Assess Understanding in Intermediate Physics Courses

NASA Astrophysics Data System (ADS)

Johnston, Marty; Jalkio, Jeffrey

2013-04-01

By the time students have reached the intermediate level physics courses they have been exposed to a broad set of analytical, experimental, and computational skills. However, their ability to independently integrate these skills into the study of a physical system is often weak. To address this weakness and assess their understanding of the underlying physical concepts we have introduced laboratory homework into lecture based, junior level theoretical mechanics and electromagnetics courses. A laboratory homework set replaces a traditional one and emphasizes the analysis of a single system. In an exercise, students use analytical and computational tools to predict the behavior of a system and design a simple measurement to test their model. The laboratory portion of the exercises is straight forward and the emphasis is on concept integration and application. The short student reports we collect have revealed misconceptions that were not apparent in reviewing the traditional homework and test problems. Work continues on refining the current problems and expanding the problem sets.

CH-π Interaction Driven Macroscopic Property Transition on Smart Polymer Surface

NASA Astrophysics Data System (ADS)

Li, Minmin; Qing, Guangyan; Xiong, Yuting; Lai, Yuekun; Sun, Taolei

2015-10-01

Life systems have evolved to utilize weak noncovalent interactions, particularly CH-π interaction, to achieve various biofunctions, for example cellular communication, immune response, and protein folding. However, for artificial materials, it remains a great challenge to recognize such weak interaction, further transform it into tunable macroscopic properties and realize special functions. Here we integrate monosaccharide-based CH-π receptor capable of recognizing aromatic peptides into a smart polymer with three-component “Recognition-Mediating-Function” design, and report the CH-π interaction driven surface property switching on smart polymer film, including wettability, adhesion, viscoelasticity and stiffness. Detailed studies indicate that, the CH-π interaction induces the complexation between saccharide unit and aromatic peptide, which breaks the initial amphiphilic balance of the polymer network, resulting in contraction-swelling conformational transition for polymer chains and subsequent dramatic switching in surface properties. This work not only presents a new approach to control the surface property of materials, but also points to a broader research prospect on CH-π interaction at a macroscopic level.

Elastomechanics of carbon nanotubes and their compositions

NASA Astrophysics Data System (ADS)

Yakobson, B. I.

1997-03-01

Nanotubes and their compositions have already revealed and promise more of unique mechanical properties, which are due to the three factors, corresponding to three different scales of organization. (i) The strength of the constituent C-C bonds, (ii) the spatial arrangement of these bonds within the tube layers, and (iii) the relatively weak interlayer and intertube forces. While the first has to be addressed by ab initio methods or by parameterization of empirical potentials, the important role of the two others can be investigated on a phenomenological level. Based on our shell model,(B.I. Yakobson, C. Brabec, J. Bernholc, PRL 76, 2511 (1996); also J. Comp.-Aided Mater. Design 3, 173 (1996).) we show how much can reasonably be expected for various mechanical parameters of nanotubes, in torsion, tension/compression, bending etc. Comparison with experimental data poses problems for future studies. We will discuss nanomechanics of NT compositions, their 2D and 3D arrays, largely determined by the weak lateral interactions, mostly of van Der Waals nature.

CH-π Interaction Driven Macroscopic Property Transition on Smart Polymer Surface.

PubMed

Li, Minmin; Qing, Guangyan; Xiong, Yuting; Lai, Yuekun; Sun, Taolei

2015-10-29

Life systems have evolved to utilize weak noncovalent interactions, particularly CH-π interaction, to achieve various biofunctions, for example cellular communication, immune response, and protein folding. However, for artificial materials, it remains a great challenge to recognize such weak interaction, further transform it into tunable macroscopic properties and realize special functions. Here we integrate monosaccharide-based CH-π receptor capable of recognizing aromatic peptides into a smart polymer with three-component "Recognition-Mediating-Function" design, and report the CH-π interaction driven surface property switching on smart polymer film, including wettability, adhesion, viscoelasticity and stiffness. Detailed studies indicate that, the CH-π interaction induces the complexation between saccharide unit and aromatic peptide, which breaks the initial amphiphilic balance of the polymer network, resulting in contraction-swelling conformational transition for polymer chains and subsequent dramatic switching in surface properties. This work not only presents a new approach to control the surface property of materials, but also points to a broader research prospect on CH-π interaction at a macroscopic level.

Experiments and Model for Serration Statistics in Low-Entropy, Medium-Entropy, and High-Entropy Alloys

DOE PAGES

Carroll, Robert; Lee, Chi; Tsai, Che-Wei; ...

2015-11-23

In this study, high-entropy alloys (HEAs) are new alloys that contain five or more elements in roughly-equal proportion. We present new experiments and theory on the deformation behavior of HEAs under slow stretching (straining), and observe differences, compared to conventional alloys with fewer elements. For a specific range of temperatures and strain-rates, HEAs deform in a jerky way, with sudden slips that make it difficult to precisely control the deformation. An analytic model explains these slips as avalanches of slipping weak spots and predicts the observed slip statistics, stress-strain curves, and their dependence on temperature, strain-rate, and material composition. Themore » ratio of the weak spots’ healing rate to the strain-rate is the main tuning parameter, reminiscent of the Portevin- LeChatellier effect and time-temperature superposition in polymers. Our model predictions agree with the experimental results. The proposed widely-applicable deformation mechanism is useful for deformation control and alloy design.« less

Risk-Adjusted Returns and Stock Market Games.

ERIC Educational Resources Information Center

Kagan, Gary; And Others

1995-01-01

Maintains that stock market games are designed to provide students with a background for investing in securities, especially stocks. Reviews two games used with secondary students, analyzes statistical data from these experiences, and considers weaknesses in the games. (CFR)

An update on the relationship between statins and physical activity.

PubMed

Panza, Gregory A; Taylor, Beth A; Thompson, Paul D

2016-09-01

This review examined studies published within the last 16 months that investigated the relationship between statins and physical activity. These recent studies suggest that statins do not adversely affect cardiorespiratory fitness, muscle strength, athletic performance, or physical activity adherence. One recent study comparing patients with statin-associated myalgia and nonstatin-using controls did report that statins are associated with a slowing of time to peak power output, increased abdominal adiposity, and insulin resistance. Statin users also had different muscle gene expression than controls, but conclusions are limited by the design of that study. Previous reports suggest that statin-associated muscle symptoms such as myalgia, cramps, and weakness occur more frequently in physically active individuals, but the recent studies we reviewed do not provide additional support for this possibility. Well-designed clinical trials are needed to determine whether different statins or statin doses evoke statin-associated muscle symptoms or muscle damage that may reduce cardiorespiratory fitness and adherence to physical activity.

Healthy urban environments for children and young people: A systematic review of intervention studies.

PubMed

Audrey, Suzanne; Batista-Ferrer, Harriet

2015-11-01

This systematic review collates, and presents as a narrative synthesis, evidence from interventions which included changes to the urban environment and reported at least one health behaviour or outcome for children and young people. Following a comprehensive search of six databases, 33 primary studies relating to 27 urban environment interventions were included. The majority of interventions related to active travel. Others included park and playground renovations, road traffic safety, and multi-component community-based initiatives. Public health evidence for effectiveness of such interventions is often weak because study designs tend to be opportunistic, non-randomised, use subjective outcome measures, and do not incorporate follow-up of study participants. However, there is some evidence of potential health benefits to children and young people from urban environment interventions relating to road safety and active travel, with evidence of promise for a multi-component obesity prevention initiative. Future research requires more robust study designs incorporating objective outcome measures. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Design of Meter-Scale Antenna and Signal Detection System for Underground Magnetic Resonance Sounding in Mines.

PubMed

Yi, Xiaofeng; Zhang, Jian; Fan, Tiehu; Tian, Baofeng; Jiang, Chuandong

2018-03-13

Magnetic resonance sounding (MRS) is a novel geophysical method to detect groundwater directly. By applying this method to underground projects in mines and tunnels, warning information can be provided on water bodies that are hidden in front prior to excavation and thus reduce the risk of casualties and accidents. However, unlike its application to ground surfaces, the application of MRS to underground environments is constrained by the narrow space, quite weak MRS signal, and complex electromagnetic interferences with high intensities in mines. Focusing on the special requirements of underground MRS (UMRS) detection, this study proposes the use of an antenna with different turn numbers, which employs a separated transmitter and receiver. We designed a stationary coil with stable performance parameters and with a side length of 2 m, a matching circuit based on a Q-switch and a multi-stage broad/narrowband mixed filter that can cancel out most electromagnetic noise. In addition, noises in the pass-band are further eliminated by adopting statistical criteria and harmonic modeling and stacking, all of which together allow weak UMRS signals to be reliably detected. Finally, we conducted a field case study of the UMRS measurement in the Wujiagou Mine in Shanxi Province, China, with known water bodies. Our results show that the method proposed in this study can be used to obtain UMRS signals in narrow mine environments, and the inverted hydrological information generally agrees with the actual situation. Thus, we conclude that the UMRS method proposed in this study can be used for predicting hazardous water bodies at a distance of 7-9 m in front of the wall for underground mining projects.

Design of Meter-Scale Antenna and Signal Detection System for Underground Magnetic Resonance Sounding in Mines

PubMed Central

Yi, Xiaofeng; Fan, Tiehu; Tian, Baofeng

2018-01-01

Magnetic resonance sounding (MRS) is a novel geophysical method to detect groundwater directly. By applying this method to underground projects in mines and tunnels, warning information can be provided on water bodies that are hidden in front prior to excavation and thus reduce the risk of casualties and accidents. However, unlike its application to ground surfaces, the application of MRS to underground environments is constrained by the narrow space, quite weak MRS signal, and complex electromagnetic interferences with high intensities in mines. Focusing on the special requirements of underground MRS (UMRS) detection, this study proposes the use of an antenna with different turn numbers, which employs a separated transmitter and receiver. We designed a stationary coil with stable performance parameters and with a side length of 2 m, a matching circuit based on a Q-switch and a multi-stage broad/narrowband mixed filter that can cancel out most electromagnetic noise. In addition, noises in the pass-band are further eliminated by adopting statistical criteria and harmonic modeling and stacking, all of which together allow weak UMRS signals to be reliably detected. Finally, we conducted a field case study of the UMRS measurement in the Wujiagou Mine in Shanxi Province, China, with known water bodies. Our results show that the method proposed in this study can be used to obtain UMRS signals in narrow mine environments, and the inverted hydrological information generally agrees with the actual situation. Thus, we conclude that the UMRS method proposed in this study can be used for predicting hazardous water bodies at a distance of 7–9 m in front of the wall for underground mining projects. PMID:29534007

The research questions and methodological adequacy of clinical studies of the voice and larynx published in Brazilian and international journals.

PubMed

Vieira, Vanessa Pedrosa; De Biase, Noemi; Peccin, Maria Stella; Atallah, Alvaro Nagib

2009-06-01

To evaluate the methodological adequacy of voice and laryngeal study designs published in speech-language pathology and otorhinolaryngology journals indexed for the ISI Web of Knowledge (ISI Web) and the MEDLINE database. A cross-sectional study conducted at the Universidade Federal de São Paulo (Federal University of São Paulo). Two Brazilian speech-language pathology and otorhinolaryngology journals (Pró-Fono and Revista Brasileira de Otorrinolaringologia) and two international speech-language pathology and otorhinolaryngology journals (Journal of Voice, Laryngoscope), all dated between 2000 and 2004, were hand-searched by specialists. Subsequently, voice and larynx publications were separated, and a speech-language pathologist and otorhinolaryngologist classified 374 articles from the four journals according to objective and study design. The predominant objective contained in the articles was that of primary diagnostic evaluation (27%), and the most frequent study design was case series (33.7%). A mere 7.8% of the studies were designed adequately with respect to the stated objectives. There was no statistical difference in the methodological quality of studies indexed for the ISI Web and the MEDLINE database. The studies published in both national journals, indexed for the MEDLINE database, and international journals, indexed for the ISI Web, demonstrate weak methodology, with research poorly designed to meet the proposed objectives. There is much scientific work to be done in order to decrease uncertainty in the field analysed.

$$\\chi$$EFT studies of few-nucleon systems: a status report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schiavilla, Rocco

2016-06-01

A status report onmore » $$\\chi$$EFT studies of few-nucleon electroweak structure and dynamics is provided, including electromagnetic elastic form factors of few-nucleon systems, the $pp$ weak fusion and muon weak captures on deuteron and $^3$He, and a number of parity-violating processes induced by hadronic weak interactions.« less

Weak Gravitational Lensing by the Nearby Cluster Abell 3667.

PubMed

Joffre; Fischer; Frieman; McKay; Mohr; Nichol; Johnston; Sheldon; Bernstein

2000-05-10

We present two weak lensing reconstructions of the nearby (zcl=0.055) merging cluster Abell 3667, based on observations taken approximately 1 yr apart under different seeing conditions. This is the lowest redshift cluster with a weak lensing mass reconstruction to date. The reproducibility of features in the two mass maps demonstrates that weak lensing studies of low-redshift clusters are feasible. These data constitute the first results from an X-ray luminosity-selected weak lensing survey of 19 low-redshift (z<0.1) southern clusters.

Neutron Measurements and the Weak Nucleon-Nucleon Interaction

PubMed Central

Snow, W. M.

2005-01-01

The weak interaction between nucleons remains one of the most poorly-understood sectors of the Standard Model. A quantitative description of this interaction is needed to understand weak interaction phenomena in atomic, nuclear, and hadronic systems. This paper summarizes briefly what is known about the weak nucleon-nucleon interaction, tries to place this phenomenon in the context of other studies of the weak and strong interactions, and outlines a set of measurements involving low energy neutrons which can lead to significant experimental progress. PMID:27308120

A practical approach to programmatic assessment design.

PubMed

Timmerman, A A; Dijkstra, J

2017-12-01

Assessment of complex tasks integrating several competencies calls for a programmatic design approach. As single instruments do not provide the information required to reach a robust judgment of integral performance, 73 guidelines for programmatic assessment design were developed. When simultaneously applying these interrelated guidelines, it is challenging to keep a clear overview of all assessment activities. The goal of this study was to provide practical support for applying a programmatic approach to assessment design, not bound to any specific educational paradigm. The guidelines were first applied in a postgraduate medical training setting, and a process analysis was conducted. This resulted in the identification of four steps for programmatic assessment design: evaluation, contextualisation, prioritisation and justification. Firstly, the (re)design process starts with sufficiently detailing the assessment environment and formulating the principal purpose. Key stakeholders with sufficient (assessment) expertise need to be involved in the analysis of strengths and weaknesses and identification of developmental needs. Central governance is essential to balance efforts and stakes with the principal purpose and decide on prioritisation of design decisions and selection of relevant guidelines. Finally, justification of assessment design decisions, quality assurance and external accountability close the loop, to ensure sound underpinning and continuous improvement of the assessment programme.

Morphogenic designer--an efficient tool to digitally design tooth forms.

PubMed

Hajtó, J; Marinescu, C; Silva, N R F A

2014-01-01

Different digital software tools are available today for the purpose of designing anatomically correct anterior and posterior restorations. The current concepts present weaknesses, which can be potentially addressed by more advanced modeling tools, such as the ones already available in professional CAD (Computer Aided Design) graphical software. This study describes the morphogenic designer (MGD) as an efficient and easy method for digitally designing tooth forms for the anterior and posterior dentition. Anterior and posterior tooth forms were selected from a collection of digitalized natural teeth and subjectively assessed as "average". The models in the form of STL files were filtered, cleaned, idealized, and re-meshed to match the specifications of the software used. The shapes were then imported as wavefront ".obj" model into Modo 701, software built for modeling, texturing, visualization, and animation. In order to create a parametric design system, intentional interactive deformations were performed on the average tooth shapes and then further defined as morph targets. By combining various such parameters, several tooth shapes were formed virtually and their images presented. MGD proved to be a versatile and powerful tool for the purpose of esthetic and functional digital crown designs.

Cognitive-Processing Bias in Chinese Student Teachers with Strong and Weak Professional Identity.

PubMed

Wang, Xin-Qiang; Zhu, Jun-Cheng; Liu, Lu; Chen, Xiang-Yu

2017-01-01

Professional identity plays an important role in career development. Although many studies have examined professional identity, differences in cognitive-processing biases between Chinese student teachers with strong and weak professional identity are poorly understood. The current study adopted Tversky's social-cognitive experimental paradigm to explore cognitive-processing biases in Chinese student teachers with strong and weak professional identity. Experiment 1 showed that participants with strong professional identity exhibited stronger positive-coding bias toward positive profession-related life events, relative to that observed in those with weak professional identity. Experiment 2 showed that participants with strong professional identity exhibited greater recognition bias for previously read items, relative to that observed in those with weak professional identity. Overall, the results suggested that participants with strong professional identity exhibited greater positive cognitive-processing bias relative to that observed in those with weak professional identity.

Cognitive-Processing Bias in Chinese Student Teachers with Strong and Weak Professional Identity

PubMed Central

Wang, Xin-qiang; Zhu, Jun-cheng; Liu, Lu; Chen, Xiang-yu

2017-01-01

Professional identity plays an important role in career development. Although many studies have examined professional identity, differences in cognitive-processing biases between Chinese student teachers with strong and weak professional identity are poorly understood. The current study adopted Tversky’s social-cognitive experimental paradigm to explore cognitive-processing biases in Chinese student teachers with strong and weak professional identity. Experiment 1 showed that participants with strong professional identity exhibited stronger positive-coding bias toward positive profession-related life events, relative to that observed in those with weak professional identity. Experiment 2 showed that participants with strong professional identity exhibited greater recognition bias for previously read items, relative to that observed in those with weak professional identity. Overall, the results suggested that participants with strong professional identity exhibited greater positive cognitive-processing bias relative to that observed in those with weak professional identity. PMID:28555123

Working Memory Ability Predicts Trajectories of Early Alcohol Use in Adolescents: The Mediational Role of Impulsivity

PubMed Central

Khurana, Atika; Romer, Dan; Betancourt, Laura M.; Brodsky, Nancy L.; Giannetta, Joan M.; Hurt, Hallam

2012-01-01

Aims 1) To evaluate the role of pre-existing weakness in working memory ability (WM) as a risk factor for early alcohol use as mediated by different forms of impulsivity. 2) To assess the adverse effects of progressive alcohol use on variations in WM over time. Design, Setting and Participants A community sample of 358 adolescents [48% males, Meanage(baseline) = 11.4± 0.87 years] from a longitudinal cohort design, assessed annually over four consecutive years with less than 6% attrition. Measurements Repeated assessments were conducted for the following key variables: WM (based on performance on four separate tasks), frequency of alcohol use (AU), and three forms of impulsivity, namely sensation seeking (SS), acting-without-thinking (AWT) and delay discounting (DD). Latent growth curve modeling procedures were used to identify individual trajectories of change for all key variables. Findings Weakness in WM (at baseline) significantly predicted both concurrent alcohol use and increased frequency of use over the four waves (p <.05). This effect was entirely mediated by two forms of impulsivity, AWT and DD, both of which were characterized by underlying weakness in WM. No individual variation was observed in the slopes of WM, which suggests that individual variations in alcohol use were not associated with changes in WM in our early adolescent sample. Conclusions Early adolescent alcohol use may be a consequence of (pre-existing) weaknesses in working memory (WM) rather than a cause of it. Efforts to reduce early alcohol use should consider the distinct roles of different impulsivity dimensions, in addition to WM, as potential targets of intervention. PMID:23033972

Evaluation of biogeneric design techniques with CEREC CAD/CAM system

PubMed Central

2015-01-01

PURPOSE The aim of this study was to evaluate occlusal contacts generated by 3 different biogeneric design modes (individual (BI), copy (BC), reference (BR)) of CEREC software and to assess the designs subjectively. MATERIALS AND METHODS Ten pairs of maxillary and mandibular casts were obtained from full dentate individuals. Gypsum cast contacts were quantified with articulating paper and digital impressions were taken. Then, all ceramic crown preparation was performed on the left first molar teeth and digital impressions of prepared teeth were made. BI, BC, and BR crowns were designed. Occlusal images of designs including occlusal contacts were superimposed on the gypsum cast images and corresponding contacts were determined. Three designs were evaluated by the students. RESULTS The results of the study revealed that there was significant difference among the number of contacts of gypsum cast and digital models (P<.05). The comparison of the percentage of virtual contacts of three crown designs which were identical to the contacts of original gypsum cast revealed that BI and BR designs showed significantly higher percentages of identical contacts compared with BC design (P<.05). Subjective assessment revealed that students generally found BI designs and BR designs natural regarding naturalness of fissure morphology and cusp shape and cusp tip position. For general occlusal morphology, student groups generally found BI design "too strong" or "perfect", BC design "too weak", and BR design "perfect". CONCLUSION On a prepared tooth, three different biogeneric design modes of a CAD/CAM software reveals different crown designs regarding occlusal contacts and morphology. PMID:26816572

Psychological Treatment of Sexual Offenders Against Children: A Meta-Analytic Review of Treatment Outcome Studies.

PubMed

Grønnerød, Cato; Grønnerød, Jarna Soilevuo; Grøndahl, Pål

2015-07-01

Numerous meta-analyses and reviews have been conducted on the effectiveness of psychological treatment of sexual offenders in reducing recidivism, but no meta-analysis has been done on sexual offenders against children (SOAC) specifically. A moderate treatment effect has been shown in several evaluations of general sexual offenders, while many scholars maintain that the question remains unanswered until an adequate number of effectiveness studies with a strong research design have been carried out. In this meta-analysis, we evaluated 14 studies selected and coded according to Collaborative Outcome Data Committee (CODC) criteria. They included 1,421 adult offenders in psychotherapy and 1,509 nontreated controls, with a minimum average follow-up period of 3 years, published in peer-reviewed journals in 1980 or later. Recidivism was defined as rearrest or reconviction. Study quality was classified into strong, good, weak or rejected. The analysis revealed a treatment effect size of r = .03 for nine studies evaluated as Good or Weak, while all studies yielded an effect size of r = .08, including five studies classified as Rejected. The results show that the available research cannot establish any effect of treatment on SOAC. Despite a large amount of research, only a tiny fraction of studies meet a minimum of scientific standards, and even fewer provide sensible and useful data from which it is possible to draw conclusions. © The Author(s) 2014.

Developing a blended learning program for nursing and midwifery students in Iran: Process and preliminary outcomes.

PubMed

Zolfaghari, Mitra; Negarandeh, Reza; Eybpoosh, Sana

2013-01-01

We aimed to develop and evaluate outcomes of a blended learning (BL) program for educating nursing and midwifery students of Tehran university of medical sciences (Tehran, Iran). This was a participatory action research project. After designing BL website, providing technological infrastructures, and holding preparatory workshops, 22 blended courses were designed. BL method was implemented for one semester. Students' grade point average, participation with courses, and opinion about educational methods, and instructors' attitude and opinion about educational methods were assessed. Most students (n = 181; 72.1%) and 17 instructors (28.3%) consented to participate in the study. Students' grade point average and participation was significantly higher in BL rather than in face-to-face method (P < 0.0001). Most instructors (n = 11, 65%) had positive attitude toward BL method. Textual analysis of participants' opinion showed that most students preferred BL method and felt more independent in this method. However, they complained about lack of easy access to Internet and weakness in computer skills. Instructors admired the flexibility and incentives that had been provided in the program. However, some of them complained about the time-consuming nature of BL course design. The program showed positive effect on students' learning outcomes and participation. The strengths and weaknesses of the program should be considered for development of next phase of the project. Lessons learned in this phase might be helpful for decision makers who tend to develop similar programs in Iran. Motivational and communicational issues and users' IT skills should be addressed in every BL program.

The Langley Research Center CSI phase-0 evolutionary model testbed-design and experimental results

NASA Technical Reports Server (NTRS)

Belvin, W. K.; Horta, Lucas G.; Elliott, K. B.

1991-01-01

A testbed for the development of Controls Structures Interaction (CSI) technology is described. The design philosophy, capabilities, and early experimental results are presented to introduce some of the ongoing CSI research at NASA-Langley. The testbed, referred to as the Phase 0 version of the CSI Evolutionary model (CEM), is the first stage of model complexity designed to show the benefits of CSI technology and to identify weaknesses in current capabilities. Early closed loop test results have shown non-model based controllers can provide an order of magnitude increase in damping in the first few flexible vibration modes. Model based controllers for higher performance will need to be robust to model uncertainty as verified by System ID tests. Data are presented that show finite element model predictions of frequency differ from those obtained from tests. Plans are also presented for evolution of the CEM to study integrated controller and structure design as well as multiple payload dynamics.

Renyi entanglement entropy of interacting fermions calculated using the continuous-time quantum Monte Carlo method.

PubMed

Wang, Lei; Troyer, Matthias

2014-09-12

We present a new algorithm for calculating the Renyi entanglement entropy of interacting fermions using the continuous-time quantum Monte Carlo method. The algorithm only samples the interaction correction of the entanglement entropy, which by design ensures the efficient calculation of weakly interacting systems. Combined with Monte Carlo reweighting, the algorithm also performs well for systems with strong interactions. We demonstrate the potential of this method by studying the quantum entanglement signatures of the charge-density-wave transition of interacting fermions on a square lattice.

Porosity and Permeability Evolution Accompanying Hot fluid Injection into Diatomite, SUPRI TR-123

DOE Office of Scientific and Technical Information (OSTI.GOV)

Diabira, I.; Castanier, L.M.; Kovscek, A.R.

2001-04-19

An experimental study of silica dissolution was performed to probe the evolution of permeability and porosity in siliceous diatomite during hot fluid injection such as water or steam flooding. Two competing mechanisms were identified. Silica solubility in water at elevated temperature causes rock dissolution thereby increasing permeability; however, the rock is mechanically weak leading to compressing of the solid matrix during injection. Permeability and porosity can decrease at the onset of fluid flow. A laboratory flow apparatus was designed and built to examine these processes in diatomite core samples.

Iodine and mental development of children 5 years old and under: a systematic review and meta-analysis.

PubMed

Bougma, Karim; Aboud, Frances E; Harding, Kimberly B; Marquis, Grace S

2013-04-22

Several reviews and meta-analyses have examined the effects of iodine on mental development. None focused on young children, so they were incomplete in summarizing the effects on this important age group. The current systematic review therefore examined the relationship between iodine and mental development of children 5 years old and under. A systematic review of articles using Medline (1980-November 2011) was carried out. We organized studies according to four designs: (1) randomized controlled trial with iodine supplementation of mothers; (2) non-randomized trial with iodine supplementation of mothers and/or infants; (3) prospective cohort study stratified by pregnant women's iodine status; (4) prospective cohort study stratified by newborn iodine status. Average effect sizes for these four designs were 0.68 (2 RCT studies), 0.46 (8 non-RCT studies), 0.52 (9 cohort stratified by mothers' iodine status), and 0.54 (4 cohort stratified by infants' iodine status). This translates into 6.9 to 10.2 IQ points lower in iodine deficient children compared with iodine replete children. Thus, regardless of study design, iodine deficiency had a substantial impact on mental development. Methodological concerns included weak study designs, the omission of important confounders, small sample sizes, the lack of cluster analyses, and the lack of separate analyses of verbal and non-verbal subtests. Quantifying more precisely the contribution of iodine deficiency to delayed mental development in young children requires more well-designed randomized controlled trials, including ones on the role of iodized salt.

Preparation of water-soluble glycoconjugated poly(acrylamide) for NMR analyses of carbohydrate-carbohydrate interactions

NASA Astrophysics Data System (ADS)

Xuan, Trinh Anh; Trung, Phan Nghia; Dinh, Bui Long; Yamaguchi, Takumi; Kato, Koichi

2014-05-01

Oligosaccharide chains of glycoconjugates are important biopolymers not only as carriers of information in cell-cell interactions but also as markers of cellular differentiation, aging, and malignant alteration. Molecular interactions where carbohydrates are involved are usually considered as weak interactions, so the study and evaluation of these interactions is still in its infancy. The evidences and studies of carbohydrate-carbohydrate interactions (CCI) will be confirming the importance of this mechanism for specific cell adhesion and communication. Their development will go hand in hand with the development of new and more sensitive techniques to study weak interactions. Recently, synthetic glycopolymers with functions similar to those of such natural carbohydrates and with specific pendant saccharide moieties were used as a solution for enhancement CCI when forming polyvalent interactions. Carbohydrates are ubiquitous components of cell wall membranes and occur as glycolipids, glycoproteins, proteoglycans, and capsular polysaccharides. As such they can participate in forefront intramolecular and intracellular events. Apart from their recognized roles in the physicochemical properties of glycolipids and glycoproteins. In this study, we designed trisaccharide monomers for free radical polymerization. Subsequently, the trisaccharide unit for chemical conjugation was synthesized from galactosamine in good yield. For further NMR analyses of CCI, glycopolymers composed of these sugar derivatives will be provided.

Pre-admission criteria and pre-clinical achievement: Can they predict medical students performance in the clinical phase?

PubMed

Salem, Raneem O; Al-Mously, Najwa; AlFadil, Sara; Baalash, Amal

2016-01-01

Various factors affect medical students' performance during clinical phase. Identifying these factors would help in mentoring weak students and help in selection process for residency programmes. Our study objective is to evaluate the impact of pre-admission criteria, and pre-clinical grade point average (GPA) on undergraduate medical students' performance during clinical phase. This study has a cross-sectional design that includes fifth- and sixth-year female medical students (71). Data of clinical and pre-clinical GPA in medical school and pre-admission to medical school tests scores were collected. A significant correlation between clinical GPA with the pre-clinical GPA was observed (p < 0.05). Such significant correlation was not seen with other variables under study. A regression analysis was performed, and the only significant predictor of students clinical performance was the pre-clinical GPA (p < 0.001). However, no significant difference between students' clinical and pre-clinical GPA for both cohorts was observed (p > 0.05). Pre-clinical GPA is strongly correlated with and can predict medical students' performance during clinical years. Our study highlighted the importance of evaluating the academic performances of students in pre-clinical years before they move into clinical years in order to identify weak students to mentor them and monitor their progress.

Objectively measured physical activity has a negative but weak association with academic performance in children and adolescents.

PubMed

Esteban-Cornejo, Irene; Tejero-González, Carlos M; Martinez-Gomez, David; Cabanas-Sánchez, Verónica; Fernández-Santos, Jorge R; Conde-Caveda, Julio; Sallis, James F; Veiga, Oscar L

2014-11-01

There is an emerging body of evidence on the potential effects of regular physical activity on academic performance. The aim of this study was to add to the debate, by examining the association between objectively measured physical activity and academic performance in a relatively large sample of children and adolescents. The Spanish UP & DOWN study is a 3-year longitudinal study designed to assess the impact, overtime, of physical activity and sedentary behaviours on health indicators. This present analysis was conducted with 1778 children and adolescents aged 6-18 years. Physical activity was objectively measured by accelerometry. Academic performance was assessed using school grades. Physical activity was inversely associated with all academic performance indicators after adjustment for potential confounders, including neonatal variables, fatness and fitness (all p < 0.05). This association became nonsignificant among quartiles of physical activity. There were only slight differences in academic performance between the lowest and the second quartile of physical activity, compared to the highest quartile, with very small effect size (d < 0.20). Objectively measured physical activity may influence academic performance during both childhood and adolescence, but this association was negative and very weak. Longitudinal and intervention studies are necessary to further our understanding. ©2014 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

From a Trickle to a Flood: Active Attacks on Several Mix Types

DTIC Science & Technology

2002-01-01

out potential weaknesses in existing designs, and suggest improvements. 1 Introduction Many modern anonymity systems are based on mixes. Chaum first...Enhancing Technologies: Proceedings of the International Workshop on the Design Issues in Anonymity and Observability, pages 10–29, July 2000. 2. David ... Chaum . Untraceable electronic mail, return addresses and digital pseudonyms. Communications of the ACM, 24(2):84–88, 1981. 3. L. Cottrell. Mixmaster

Weak interactions, omnivory and emergent food-web properties.

PubMed

Emmerson, Mark; Yearsley, Jon M

2004-02-22

Empirical studies have shown that, in real ecosystems, species-interaction strengths are generally skewed in their distribution towards weak interactions. Some theoretical work also suggests that weak interactions, especially in omnivorous links, are important for the local stability of a community at equilibrium. However, the majority of theoretical studies use uniform distributions of interaction strengths to generate artificial communities for study. We investigate the effects of the underlying interaction-strength distribution upon the return time, permanence and feasibility of simple Lotka-Volterra equilibrium communities. We show that a skew towards weak interactions promotes local and global stability only when omnivory is present. It is found that skewed interaction strengths are an emergent property of stable omnivorous communities, and that this skew towards weak interactions creates a dynamic constraint maintaining omnivory. Omnivory is more likely to occur when omnivorous interactions are skewed towards weak interactions. However, a skew towards weak interactions increases the return time to equilibrium, delays the recovery of ecosystems and hence decreases the stability of a community. When no skew is imposed, the set of stable omnivorous communities shows an emergent distribution of skewed interaction strengths. Our results apply to both local and global concepts of stability and are robust to the definition of a feasible community. These results are discussed in the light of empirical data and other theoretical studies, in conjunction with their broader implications for community assembly.

Progress in multidisciplinary design optimization at NASA Langley

NASA Technical Reports Server (NTRS)

Padula, Sharon L.

1993-01-01

Multidisciplinary Design Optimization refers to some combination of disciplinary analyses, sensitivity analysis, and optimization techniques used to design complex engineering systems. The ultimate objective of this research at NASA Langley Research Center is to help the US industry reduce the costs associated with development, manufacturing, and maintenance of aerospace vehicles while improving system performance. This report reviews progress towards this objective and highlights topics for future research. Aerospace design problems selected from the author's research illustrate strengths and weaknesses in existing multidisciplinary optimization techniques. The techniques discussed include multiobjective optimization, global sensitivity equations and sequential linear programming.

A spatio-temporal model of the human observer for use in display design

NASA Astrophysics Data System (ADS)

Bosman, Dick

1989-08-01

A "quick look" visual model, a kind of standard observer in software, is being developed to estimate the appearance of new display designs before prototypes are built. It operates on images also stored in software. It is assumed that the majority of display design flaws and technology artefacts can be identified in representations of early visual processing, and insight obtained into very local to global (supra-threshold) brightness distributions. Cognitive aspects are not considered because it seems that poor acceptance of technology and design is only weakly coupled to image content.

Increasing value and reducing waste in research design, conduct, and analysis.

PubMed

Ioannidis, John P A; Greenland, Sander; Hlatky, Mark A; Khoury, Muin J; Macleod, Malcolm R; Moher, David; Schulz, Kenneth F; Tibshirani, Robert

2014-01-11

Correctable weaknesses in the design, conduct, and analysis of biomedical and public health research studies can produce misleading results and waste valuable resources. Small effects can be difficult to distinguish from bias introduced by study design and analyses. An absence of detailed written protocols and poor documentation of research is common. Information obtained might not be useful or important, and statistical precision or power is often too low or used in a misleading way. Insufficient consideration might be given to both previous and continuing studies. Arbitrary choice of analyses and an overemphasis on random extremes might affect the reported findings. Several problems relate to the research workforce, including failure to involve experienced statisticians and methodologists, failure to train clinical researchers and laboratory scientists in research methods and design, and the involvement of stakeholders with conflicts of interest. Inadequate emphasis is placed on recording of research decisions and on reproducibility of research. Finally, reward systems incentivise quantity more than quality, and novelty more than reliability. We propose potential solutions for these problems, including improvements in protocols and documentation, consideration of evidence from studies in progress, standardisation of research efforts, optimisation and training of an experienced and non-conflicted scientific workforce, and reconsideration of scientific reward systems. Copyright © 2014 Elsevier Ltd. All rights reserved.

Literary Reading Activities of Good and Weak Students: A Think Aloud Study

ERIC Educational Resources Information Center

Janssen, Tanja; Braaksma, Martine; Rijlaarsdam, Gert

2006-01-01

In this study we examined how good and weak students of literature interact with short literary stories. We focused on differences in the use of cognitive and affective reading activities, and in the extent to which good and weak students adapt their activities to (parts of) the story they are reading. 19 Dutch tenth-grade students from 8 classes…

The SAZA study: implementing health financing reform in South Africa and Zambia.

PubMed

Gilson, Lucy; Doherty, Jane; Lake, Sally; McIntyre, Di; Mwikisa, Chris; Thomas, Stephen

2003-03-01

This paper explores the policy-making process in the 1990s in two countries, South Africa and Zambia, in relation to health care financing reforms. While much of the analysis of health reform programmes has looked at design issues, assuming that a technically sound design is the primary requirement of effective policy change, this paper explores the political and bureaucratic realities shaping the pattern of policy change and its impacts. Through a case study approach, it provides a picture of the policy environment and processes in the two countries, specifically considering the extent to which technical analysts and technical knowledge were able to shape policy change. The two countries' experiences indicate the strong influence of political factors and actors over which health care financing policies were implemented, and which not, as well as over the details of policy design. Moments of political transition in both countries provided political leaders, specifically Ministers of Health, with windows of opportunity in which to introduce new policies. However, these transitions, and the changes in administrative structures introduced with them, also created environments that constrained the processes of reform design and implementation and limited the equity and sustainability gains achieved by the policies. Technical analysts, working either inside or outside government, had varying and often limited influence. In part, this reflected the limits of their own capacity as well as weaknesses in the way they were used in policy development. In addition, the analysts were constrained by the fact that their preferred policies often received only weak political support. Focusing almost exclusively on designing policy reforms, these analysts gave little attention to generating adequate support for the policy options they proposed. Finally, the country experiences showed that front-line health workers, middle level managers and the public had important influences over policy implementation and its impacts. The limited attention given to communicating policy changes to, or consulting with, these actors only heightened the potential for reforms to result in unanticipated and unwanted impacts. The strength of the paper lies in its 'thick description' of the policy process in each country, an empirical case study approach to policy that is under-represented in the literature. While such an approach allows only a cautious drawing of general conclusions, it suggests a number of ways in which to strengthen the implementation of financing policies in each country.

A note on libration point orbits, temporary capture and low-energy transfers

NASA Astrophysics Data System (ADS)

Fantino, E.; Gómez, G.; Masdemont, J. J.; Ren, Y.

2010-11-01

In the circular restricted three-body problem (CR3BP) the weak stability boundary (WSB) is defined as a boundary set in the phase space between stable and unstable motion relative to the second primary. At a given energy level, the boundaries of such region are provided by the stable manifolds of the central objects of the L1 and L2 libration points, i.e., the two planar Lyapunov orbits. Besides, the unstable manifolds of libration point orbits (LPOs) around L1 and L2 have been identified as responsible for the weak or temporary capture around the second primary of the system. These two issues suggest the existence of natural dynamical channels between the Earth's vicinity and the Sun-Earth libration points L1 and L2. Furthermore, it has been shown that the Sun-Earth L2 central unstable manifolds can be linked, through an heteroclinic connection, to the central stable manifolds of the L2 point in the Earth-Moon three-body problem. This concept has been applied to the design of low energy transfers (LETs) from the Earth to the Moon. In this contribution we consider all the above three issues, i.e., weak stability boundaries, temporary capture and low energy transfers, and we discuss the role played by the invariant manifolds of LPOs in each of them. The study is made in the planar approximation.

Weak-interaction rates in stellar conditions

NASA Astrophysics Data System (ADS)

Sarriguren, Pedro

2018-05-01

Weak-interaction rates, including β-decay and electron captures, are studied in several mass regions at various densities and temperatures of astrophysical interest. In particular, we study odd-A nuclei in the pf-shell region, which are involved in presupernova formations. Weak rates are relevant to understand the late stages of the stellar evolution, as well as the nucleosynthesis of heavy nuclei. The nuclear structure involved in the weak processes is studied within a quasiparticle proton-neutron random-phase approximation with residual interactions in both particle-hole and particle-particle channels on top of a deformed Skyrme Hartree-Fock mean field with pairing correlations. First, the energy distributions of the Gamow-Teller strength are discussed and compared with the available experimental information, measured under terrestrial conditions from charge-exchange reactions. Then, the sensitivity of the weak-interaction rates to both astrophysical densities and temperatures is studied. Special attention is paid to the relative contribution to these rates of thermally populated excited states in the decaying nucleus and to the electron captures from the degenerate electron plasma.

Nursing Doctorates in Brazil: research formation and theses production.

PubMed

Scochi, Carmen Gracinda Silvan; Gelbcke, Francine Lima; Ferreira, Márcia de Assunção; Lima, Maria Alice Dias da Silva; Padilha, Katia Grillo; Padovani, Nátali Artal; Munari, Denize Bouttelet

2015-01-01

to analyze the formation of nursing doctorates in Brazil, from theses production, disciplines and other strategies focusing on research offered by courses. a descriptive and analytical study of the performance of 18 doctoral courses in nursing, running from 1982 to 2010, and defended their theses between 2010-2012. 502 theses were defended in this period, most linked to the online research process of health and nursing care. There are gaps in the knowledge of theoretical and philosophical foundations of care, nursing history and ethics. There are also weaknesses in the methodological design of the theses, with a predominance of descriptive and/or exploratory studies. This was consistent with international standards set with regards to the proposition of research of disciplines and complementary strategies in forming the doctorate. despite the efforts and advances in research formation, it is essential to expand to more robust research designs with a greater impact on production knowledge that is incorporated into practice.

Global analysis of protein folding using massively parallel design, synthesis and testing

PubMed Central

Rocklin, Gabriel J.; Chidyausiku, Tamuka M.; Goreshnik, Inna; Ford, Alex; Houliston, Scott; Lemak, Alexander; Carter, Lauren; Ravichandran, Rashmi; Mulligan, Vikram K.; Chevalier, Aaron; Arrowsmith, Cheryl H.; Baker, David

2017-01-01

Proteins fold into unique native structures stabilized by thousands of weak interactions that collectively overcome the entropic cost of folding. Though these forces are “encoded” in the thousands of known protein structures, “decoding” them is challenging due to the complexity of natural proteins that have evolved for function, not stability. Here we combine computational protein design, next-generation gene synthesis, and a high-throughput protease susceptibility assay to measure folding and stability for over 15,000 de novo designed miniproteins, 1,000 natural proteins, 10,000 point-mutants, and 30,000 negative control sequences, identifying over 2,500 new stable designed proteins in four basic folds. This scale—three orders of magnitude greater than that of previous studies of design or folding—enabled us to systematically examine how sequence determines folding and stability in uncharted protein space. Iteration between design and experiment increased the design success rate from 6% to 47%, produced stable proteins unlike those found in nature for topologies where design was initially unsuccessful, and revealed subtle contributions to stability as designs became increasingly optimized. Our approach achieves the long-standing goal of a tight feedback cycle between computation and experiment, and promises to transform computational protein design into a data-driven science. PMID:28706065

Direct quantum process tomography via measuring sequential weak values of incompatible observables.

PubMed

Kim, Yosep; Kim, Yong-Su; Lee, Sang-Yun; Han, Sang-Wook; Moon, Sung; Kim, Yoon-Ho; Cho, Young-Wook

2018-01-15

The weak value concept has enabled fundamental studies of quantum measurement and, recently, found potential applications in quantum and classical metrology. However, most weak value experiments reported to date do not require quantum mechanical descriptions, as they only exploit the classical wave nature of the physical systems. In this work, we demonstrate measurement of the sequential weak value of two incompatible observables by making use of two-photon quantum interference so that the results can only be explained quantum physically. We then demonstrate that the sequential weak value measurement can be used to perform direct quantum process tomography of a qubit channel. Our work not only demonstrates the quantum nature of weak values but also presents potential new applications of weak values in analyzing quantum channels and operations.

Biology of Bilirubin Photoisomers.

PubMed

Hansen, Thor Willy Ruud

2016-06-01

Phototherapy is the main treatment for neonatal hyperbilirubinemia. In acute treatment of extreme hyperbilirubinemia, intensive phototherapy may have a role in 'detoxifying' the bilirubin molecule to more polar photoisomers, which should be less prone to crossing the blood-brain barrier, providing a 'brain-sparing' effect. This article reviews the biology of bilirubin isomers. Although there is evidence supporting the lower toxicity of bilirubin photoisomers, there are studies showing the opposite. There are methodologic weaknesses in most studies and better-designed experiments are needed. In an infant acutely threatened by bilirubin-induced brain damage, intensified phototherapy should be used expediently and aggressively. Copyright © 2016 Elsevier Inc. All rights reserved.

A theoretical model for smoking prevention studies in preteen children.

PubMed

McGahee, T W; Kemp, V; Tingen, M

2000-01-01

The age of the onset of smoking is on a continual decline, with the prime age of tobacco use initiation being 12-14 years. A weakness of the limited research conducted on smoking prevention programs designed for preteen children (ages 10-12) is a well-defined theoretical basis. A theoretical perspective is needed in order to make a meaningful transition from empirical analysis to application of knowledge. Bandura's Social Cognitive Theory (1977, 1986), the Theory of Reasoned Action (Ajzen & Fishbein, 1980), and other literature linking various concepts to smoking behaviors in preteens were used to develop a model that may be useful for smoking prevention studies in preteen children.

The role and benefits of accessing primary care patient records during unscheduled care: a systematic review.

PubMed

Bowden, Tom; Coiera, Enrico

2017-09-22

The purpose of this study was to assess the impact of accessing primary care records on unscheduled care. Unscheduled care is typically delivered in hospital Emergency Departments. Studies published to December 2014 reporting on primary care record access during unscheduled care were retrieved. Twenty-two articles met inclusion criteria from a pool of 192. Many shared electronic health records (SEHRs) were large in scale, servicing many millions of patients. Reported utilization rates by clinicians was variable, with rates >20% amongst health management organizations but much lower in nation-scale systems. No study reported on clinical outcomes or patient safety, and no economic studies of SEHR access during unscheduled care were available. Design factors that may affect utilization included consent and access models, SEHR content, and system usability and reliability. Despite their size and expense, SEHRs designed to support unscheduled care have been poorly evaluated, and it is not possible to draw conclusions about any likely benefits associated with their use. Heterogeneity across the systems and the populations they serve make generalization about system design or performance difficult. None of the reviewed studies used a theoretical model to guide evaluation. Value of Information models may be a useful theoretical approach to design evaluation metrics, facilitating comparison across systems in future studies. Well-designed SEHRs should in principle be capable of improving the efficiency, quality and safety of unscheduled care, but at present the evidence for such benefits is weak, largely because it has not been sought.

Kelvin-wave cascade in the vortex filament model

NASA Astrophysics Data System (ADS)

Baggaley, Andrew W.; Laurie, Jason

2014-01-01

The small-scale energy-transfer mechanism in zero-temperature superfluid turbulence of helium-4 is still a widely debated topic. Currently, the main hypothesis is that weakly nonlinear interacting Kelvin waves (KWs) transfer energy to sufficiently small scales such that energy is dissipated as heat via phonon excitations. Theoretically, there are at least two proposed theories for Kelvin-wave interactions. We perform the most comprehensive numerical simulation of weakly nonlinear interacting KWs to date and show, using a specially designed numerical algorithm incorporating the full Biot-Savart equation, that our results are consistent with the nonlocal six-wave KW interactions as proposed by L'vov and Nazarenko.

Friction pull plug welding: chamfered heat sink pull plug design

NASA Technical Reports Server (NTRS)

Coletta, Edmond R. (Inventor); Cantrell, Mark A. (Inventor)

2005-01-01

The average strength of a pull plug weld is increased and weak bonding eliminated by providing a dual included angle at the top one third of the pull plug. Plugs using the included angle of the present invention had consistent high strength, no weak bonds and were substantially defect free. The dual angle of the pull plug body increases the heat and pressure of the weld in the region of the top one third of the plug. This allows the plug to form a tight high quality solid state bond. The dual angle was found to be successful in elimination of defects on both small and large plugs.

Universal lineshapes at the crossover between weak and strong critical coupling in Fano-resonant coupled oscillators

NASA Astrophysics Data System (ADS)

Zanotto, Simone; Tredicucci, Alessandro

2016-04-01

In this article we discuss a model describing key features concerning the lineshapes and the coherent absorption conditions in Fano-resonant dissipative coupled oscillators. The model treats on the same footing the weak and strong coupling regimes, and includes the critical coupling concept, which is of great relevance in numerous applications; in addition, the role of asymmetry is thoroughly analyzed. Due to the wide generality of the model, which can be adapted to various frameworks like nanophotonics, plasmonics, and optomechanics, we envisage that the analytical formulas presented here will be crucial to effectively design devices and to interpret experimental results.

Finite element analysis of ROPS for mechanical driving dump truck cab

NASA Astrophysics Data System (ADS)

Wang, Yong; Xie, Heping; Fang, Yuanbin; Feng, Handui; Dong, Lei

2018-02-01

For roll-over protective structures (ROPS) in a mechanical driving dump truck cab, it simulates the lateral, vertical and longitudinal loads of ROPS. It obtains stress and deformation of the cab that occurs to roll. For the relative weak position of ROPS in the cab, the structure of the cab is improved and verified according to the ISO 3164: 1995. The results show that the established finite element model can effectively predict the deformation and stress distribution of ROPS, and optimize the weak structure of the cab, which has important guiding significance for structural design of the cab and ROPS optimization of the mechanical driving dump truck cab.

A versatile approach to the study of the transient response of a submerged thin shell

NASA Astrophysics Data System (ADS)

Leblond, C.; Sigrist, J.-F.

2010-01-01

The transient response of submerged two-dimensional thin shell subjected to weak acoustical or mechanical excitations is addressed in this paper. The proposed approach is first exposed in a detailed manner: it is based on Laplace transform in time, in vacuo eigenvector expansion with time-dependent coefficients for the structural dynamics and boundary-integral formulation for the fluid. The projection of the fluid pressure on the in vacuo eigenvectors leads to a fully coupled system involving the modal time-dependent displacement coefficients, which are the problem unknowns. They are simply determined by matrix inversion in the Laplace domain. Application of the method to the response of a two-dimensional immersed shell to a weak acoustical excitation is then exposed: the proposed test-case corresponds to the design of immersed structures subjected to underwater explosions, which is of paramount importance in naval shipbuilding. Comparison of a numerical calculation based on the proposed approach with an analytical solution is exposed; versatility of the method is also highlighted by referring to "classical" FEM/FEM or FEM/BEM simulations. As a conspicuous feature of the method, calculation of the fluid response functions corresponding to a given geometry has to be performed once, allowing various simulations for different material properties of the structure, as well as for various excitations on the structure. This versatile approach can therefore be efficiently and extensively used for design purposes.

Literature Review of Research on Chronic Pain and Yoga in Military Populations

PubMed Central

Miller, Shari; Gaylord, Susan; Buben, Alex; Brintz, Carrie; Rae Olmsted, Kristine; Asefnia, Nakisa; Bartoszek, Michael

2017-01-01

Background: Although yoga is increasingly being provided to active duty soldiers and veterans, studies with military populations are limited and effects on chronic pain are largely unknown. We reviewed the existing body of literature and provide recommendations for future research. Methods: We conducted a literature review of electronic databases (PubMed, PsychINFO, Web of Science, Science Citation Index Expanded, Social Sciences Citation Index, Conference Proceedings Citation Index—Science, and Conference Proceedings Citation Index—Social Science & Humanities). The studies were reviewed for characteristics such as mean age of participants, sample size, yoga type, and study design. Only peer-reviewed studies were included in the review. Results: The search yielded only six studies that examined pain as an outcome of yoga for military populations. With one exception, studies were with veteran populations. Only one study was conducted with Operation Enduring Freedom (OEF) or Operation Iraqi Freedom (OIF) veterans. One study was a randomized controlled trial (RCT). Four of the five studies remaining used pre/post design, while the last study used a post-only design. Conclusions: Studies on the use of yoga to treat chronic pain in military populations are in their infancy. Methodological weaknesses include small sample sizes, a lack of studies with key groups (active duty, OEF/IEF veterans), and use of single group uncontrolled designs (pre/post; post only) for all but one study. Future research is needed to address these methodological limitations and build on this small body of literature. PMID:28930278

Partial recovery of peristalsis after myotomy for achalasia; more the rule than the exception

PubMed Central

Roman, Sabine; Kahrilas, Peter J; Mion, François; Nealis, Thomas B; Soper, Nathaniel J; Poncet, Gilles; Nicodème, Frédéric; Hungness, Eric; Pandolfino, John E

2013-01-01

Hypothesis: Myotomy that alleviates the esophagogastric junction (EGJ) outflow obstruction in achalasia might improve peristalsis. Design: Retrospective study Setting: Two tertiary hospitals (Chicago, USA and Lyon, France) Patients: Thirty patients (18 males; mean age 43 years, range 17-78) were included from 2004 to 2012: 8 type 1 achalasia (27%), 17 type 2 (57%) and 5 type 3 (16%) according to the Chicago Classification. Interventions: Esophageal high resolution manometry (HRM) before and after laparoscopic or endoscopic myotomy. Main outcomes measures: The integrity of peristalsis was characterized as intact, weak, frequent failed, absent, or premature contractions. Results: Whereas peristaltic fragments were evident only in patients with type 3 achalasia before treatment, intact, weak, or frequent failed peristalsis was encountered in 63% of type 1, 47% of type 2 and 80% of type 3 achalasia after myotomy. One type 3 patient had distal esophageal spasm after treatment. In patients with a post-myotomy integrated relaxation pressure (IRP) <15 mmHg, only 10 (40%) persisted in having absent peristalsis. Panesophageal pressurization disappeared after myotomy in 16 of 19 patients. In the 5 patients with post-myotomy IRP >15 mmHg, 4 had weak peristalsis and one had absent peristalsis. Conclusion: Reduction or normalization of the EGJ relaxation pressure achieved by myotomy in achalasia patients was associated with partial recovery of peristalsis in some patients suggesting that the disease process progresses from the EGJ to the esophageal body. Whether or not the return of peristalsis is predictive of an improved therapeutic outcome requires further study. PMID:23426591

A multi-wavelength investigation of Seyfert 1.8 and 1.9 galaxies

NASA Astrophysics Data System (ADS)

Trippe, Margaret L.

We focus on determining the underlying physical cause of a Seyfert galaxy's appearance as type a 1.8 or 1.9. Are these "intermediate" Seyfert types typical Seyfert 1 nuclei reddened by central dusty tori or by nuclear dust lanes/spirals in the narrow-line region? Or, are they similar to NGC 2992, objects that have intrinsically weak continua and weak broad emission lines? Our study compares measurements of the reddenings of the narrow and broad-line regions with each other and with the X-ray column derived from XMM Newton 0.5--10 keV spectra to determine the presence and location of dust in the line of sight for a sample of 35 Seyfert 1.8s and 1.9s. From this, we find that Seyfert 1.9s are an almost equal mix of low-flux objects with unreddened broad line regions, and objects with broad line regions reddened by an internal dust source, either the torus or dust structures on the same size scale as the narrow line region. The 1.9s that recieved this designation due to a low continuum flux state showed variable type classifications. All three of the Seyfert 1.8s in our study are probably in low continuum states. Many objects have been misclassified as Seyfert 1.8/1.9s in the past, probably due to improper [N II]/Halpha deconvolution leading to a false detection of weak broad Halpha. INDEX WORDS: Active galaxies, Seyfert galaxies, Optical spectroscopy, X-ray spectroscopy, Astronomical dust

Long-term Behavioral Tracking of Freely Swimming Weakly Electric Fish

PubMed Central

Jun, James J.; Longtin, André; Maler, Leonard

2014-01-01

Long-term behavioral tracking can capture and quantify natural animal behaviors, including those occurring infrequently. Behaviors such as exploration and social interactions can be best studied by observing unrestrained, freely behaving animals. Weakly electric fish (WEF) display readily observable exploratory and social behaviors by emitting electric organ discharge (EOD). Here, we describe three effective techniques to synchronously measure the EOD, body position, and posture of a free-swimming WEF for an extended period of time. First, we describe the construction of an experimental tank inside of an isolation chamber designed to block external sources of sensory stimuli such as light, sound, and vibration. The aquarium was partitioned to accommodate four test specimens, and automated gates remotely control the animals' access to the central arena. Second, we describe a precise and reliable real-time EOD timing measurement method from freely swimming WEF. Signal distortions caused by the animal's body movements are corrected by spatial averaging and temporal processing stages. Third, we describe an underwater near-infrared imaging setup to observe unperturbed nocturnal animal behaviors. Infrared light pulses were used to synchronize the timing between the video and the physiological signal over a long recording duration. Our automated tracking software measures the animal's body position and posture reliably in an aquatic scene. In combination, these techniques enable long term observation of spontaneous behavior of freely swimming weakly electric fish in a reliable and precise manner. We believe our method can be similarly applied to the study of other aquatic animals by relating their physiological signals with exploratory or social behaviors. PMID:24637642

ForwArd Search ExpeRiment at the LHC

NASA Astrophysics Data System (ADS)

Feng, Jonathan L.; Galon, Iftah; Kling, Felix; Trojanowski, Sebastian

2018-02-01

New physics has traditionally been expected in the high-pT region at high-energy collider experiments. If new particles are light and weakly coupled, however, this focus may be completely misguided: light particles are typically highly concentrated within a few mrad of the beam line, allowing sensitive searches with small detectors, and even extremely weakly coupled particles may be produced in large numbers there. We propose a new experiment, forward search experiment, or FASER, which would be placed downstream of the ATLAS or CMS interaction point (IP) in the very forward region and operated concurrently there. Two representative on-axis locations are studied: a far location, 400 m from the IP and just off the beam tunnel, and a near location, just 150 m from the IP and right behind the TAN neutral particle absorber. For each location, we examine leading neutrino- and beam-induced backgrounds. As a concrete example of light, weakly coupled particles, we consider dark photons produced through light meson decay and proton bremsstrahlung. We find that even a relatively small and inexpensive cylindrical detector, with a radius of ˜10 cm and length of 5-10 m, depending on the location, can discover dark photons in a large and unprobed region of parameter space with dark photon mass mA'˜10 - 500 MeV and kinetic mixing parameter ɛ ˜10-6-10-3. FASER will clearly also be sensitive to many other forms of new physics. We conclude with a discussion of topics for further study that will be essential for understanding FASER's feasibility, optimizing its design, and realizing its discovery potential.

Outcome of Guillain–Barre syndrome patients with respiratory paralysis

PubMed Central

Kalita, J.; Ranjan, A.

2016-01-01

Background and Aims: To evaluate the outcome of patients with Guillain–Barre syndrome (GBS) having respiratory failure treated with modified intubation policy. Design and Methods: Consecutive patients with GBS having single breath count below 12 and respiratory rate >30/min were included and their clinical details noted. The patients were intubated and mechanically ventilated (MV) if their PaO2 was <60 mmHg on venturi mask, PaCo2 > 50 mmHg or pH < 7.3. Their electrophysiological subtypes and complications were noted. The hospital mortality and 3 months outcome were compared in MV and those could be managed without MV even with respiratory compromise. Results: Out of 369 patients, 102 (27.6%) patients had respiratory compromise who were included in this study. Of the patients with respiratory compromise, 44 (43.1%) were intubated and mechanically ventilated after a median of 4 days of hospitalization. The median duration of MV was 21 (range 1–88) days. The patients with autonomic dysfunction (56.8% vs. 19%), facial weakness (78% vs. 36.2%), bulbar weakness (81.8% vs. 31%), severe weakness (63.8% vs. 31%) and high transaminase level (47.7% vs. 25.9%) needed MV more frequently. In our study, 6.8% patients died and 26.6% had poor outcome which was similar between MV and non-MV patients. The MV patients had longer hospitalization and more complications compared with non-MV group. Conclusion: In GBS patients with respiratory compromise, conservative intubation does not increase mortality and disability. PMID:26475599

Assessing the Impact of Drug Use and Drug Selling on Violent Offending in a Panel of Delinquent Youth

PubMed Central

Phillips, Matthew D.

2016-01-01

Despite a vast number of empirical studies arguing for or against a causal relationship between illegal drug use and selling and violent behavior, the debate continues. In part this is due to methodological weaknesses of previous research. Using data from the Rochester Youth Development Study, the current study seeks to improve on prior research designs to allow for a more precise examination of the mechanisms that lead from an individual’s drug use (chiefly, marijuana use in the current sample) and drug selling to violent action. Results will allow for greater confidence in making causal inference regarding a long-standing concern in the discipline. PMID:26889079

76 FR 34968 - Notice of Availability for Exclusive, Non-Exclusive, or Partially; Exclusive Licensing of an...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-15

... INFORMATION: The invention relates to a dynamic exoskeletal orthosis applied to the leg below the knee, designed to compensate for weakness, pain, and/or decreased range of motion at the ankle. Brenda S. Bowen...

Quantifying stickiness: thermodynamic characterization of intramolecular domain interactions to guide the design of förster resonance energy transfer sensors.

PubMed

Lindenburg, Laurens H; Malisauskas, Mantas; Sips, Tari; van Oppen, Lisanne; Wijnands, Sjors P W; van de Graaf, Stan F J; Merkx, Maarten

2014-10-14

The introduction of weak, hydrophobic interactions between fluorescent protein domains (FPs) can substantially increase the dynamic range (DR) of Förster resonance energy transfer (FRET)-based sensor systems. Here we report a comprehensive thermodynamic characterization of the stability of a range of self-associating FRET pairs. A new method is introduced that allows direct quantification of the stability of weak FP interactions by monitoring intramolecular complex formation as a function of urea concentration. The commonly used S208F mutation stabilized intramolecular FP complex formation by 2.0 kCal/mol when studied in an enhanced cyan FP (ECFP)-linker-enhanced yellow FP (EYFP) fusion protein, whereas a significantly weaker interaction was observed for the homologous Cerulean/Citrine FRET pair (ΔG0(o-c) = 0.62 kCal/mol). The latter effect could be attributed to two mutations in Cerulean (Y145A and H148D) that destabilize complex formation with Citrine. Systematic analysis of the contribution of residues 125 and 127 at the dimerization interface in mOrange.linker.mCherry fusion proteins yielded a toolbox of new mOrange-mCherry combinations that allowed tuning of their intramolecular interaction from very weak (ΔG0(o-c) = .0.39 kCal/mol) to relatively stable (ΔG0(o-c) = 2.2 kCal/mol). The effects of these mutations were also studied by monitoring homodimerization of mCherry variants using fluorescence anisotropy. These mutations affected intramolecular and intermolecular domain interactions similarly, although FP interactions were found to be stronger in the latter. The knowledge thus obtained allowed successful construction of a red-shifted variant of the bile acid FRET sensor BAS-1 by replacement of the self-associating Cerulean-Citrine pair by mOrange.mCherry variants with a similar intramolecular affinity. Our findings thus allow a better understanding of the subtle but important role of intramolecular domain interactions in current FRET sensors and help guide the construction of new sensors using modular design strategies.

The relationship between the Early Childhood Environment Rating Scale and its revised form and child outcomes: A systematic review and meta-analysis.

PubMed

Brunsek, Ashley; Perlman, Michal; Falenchuk, Olesya; McMullen, Evelyn; Fletcher, Brooke; Shah, Prakesh S

2017-01-01

The Early Childhood Environment Rating Scale (ECERS) and its revised version (ECERS-R) were designed as global measures of quality that assess structural and process aspects of Early Childhood Education and Care (ECEC) programs. Despite frequent use of the ECERS/ECERS-R in research and applied settings, associations between it and child outcomes have not been systematically reviewed. The objective of this research was to evaluate the association between the ECERS/ECERS-R and children's wellbeing. Searches of Medline, PsycINFO, ERIC, websites of large datasets and reference sections of all retrieved articles were completed up to July 3, 2015. Eligible studies provided a statistical link between the ECERS/ECERS-R and child outcomes for preschool-aged children in ECEC programs. Of the 823 studies selected for full review, 73 were included in the systematic review and 16 were meta-analyzed. The combined sample across all eligible studies consisted of 33, 318 preschool-aged children. Qualitative systematic review results revealed that ECERS/ECERS-R total scores were more generally associated with positive outcomes than subscales or factors. Seventeen separate meta-analyses were conducted to assess the strength of association between the ECERS/ECERS-R and measures that assessed children's language, math and social-emotional outcomes. Meta-analyses revealed a small number of weak effects (in the expected direction) between the ECERS/ECERS-R total score and children's language and positive behavior outcomes. The Language-Reasoning subscale was weakly related to a language outcome. The enormous heterogeneity in how studies operationalized the ECERS/ECERS-R, the outcomes measured and statistics reported limited our ability to meta-analyze many studies. Greater consistency in study methodology is needed in this area of research. Despite these methodological challenges, the ECERS/ECERS-R does appear to capture aspects of quality that are important for children's wellbeing; however, the strength of association is weak.

The relationship between the Early Childhood Environment Rating Scale and its revised form and child outcomes: A systematic review and meta-analysis

PubMed Central

Brunsek, Ashley; Perlman, Michal; Falenchuk, Olesya; McMullen, Evelyn; Fletcher, Brooke; Shah, Prakesh S.

2017-01-01

The Early Childhood Environment Rating Scale (ECERS) and its revised version (ECERS-R) were designed as global measures of quality that assess structural and process aspects of Early Childhood Education and Care (ECEC) programs. Despite frequent use of the ECERS/ECERS-R in research and applied settings, associations between it and child outcomes have not been systematically reviewed. The objective of this research was to evaluate the association between the ECERS/ECERS-R and children’s wellbeing. Searches of Medline, PsycINFO, ERIC, websites of large datasets and reference sections of all retrieved articles were completed up to July 3, 2015. Eligible studies provided a statistical link between the ECERS/ECERS-R and child outcomes for preschool-aged children in ECEC programs. Of the 823 studies selected for full review, 73 were included in the systematic review and 16 were meta-analyzed. The combined sample across all eligible studies consisted of 33, 318 preschool-aged children. Qualitative systematic review results revealed that ECERS/ECERS-R total scores were more generally associated with positive outcomes than subscales or factors. Seventeen separate meta-analyses were conducted to assess the strength of association between the ECERS/ECERS-R and measures that assessed children’s language, math and social-emotional outcomes. Meta-analyses revealed a small number of weak effects (in the expected direction) between the ECERS/ECERS-R total score and children’s language and positive behavior outcomes. The Language-Reasoning subscale was weakly related to a language outcome. The enormous heterogeneity in how studies operationalized the ECERS/ECERS-R, the outcomes measured and statistics reported limited our ability to meta-analyze many studies. Greater consistency in study methodology is needed in this area of research. Despite these methodological challenges, the ECERS/ECERS-R does appear to capture aspects of quality that are important for children’s wellbeing; however, the strength of association is weak. PMID:28586399

Weakly-coupled 4-mode step-index FMF and demonstration of IM/DD MDM transmission.

PubMed

Hu, Tao; Li, Juhao; Ge, Dawei; Wu, Zhongying; Tian, Yu; Shen, Lei; Liu, Yaping; Chen, Su; Li, Zhengbin; He, Yongqi; Chen, Zhangyuan

2018-04-02

Weakly coupled-mode division multiplexing (MDM) over few-mode fibers (FMF) for short-reach transmission has attracted great interest, which can avoid multiple-input-multiple-output digital signal processing (MIMO-DSP) by greatly suppressing modal crosstalk. In this paper, step-index FMF supporting 4 linearity polarization (LP) modes for MIMO-free transmission is designed and fabricated for the first time, to our knowledge. Modal crosstalk of the fiber is suppressed by increasing the mode effective refractive index differences. The same fabrication method as standard single-mode fiber is adopted so that it is practical and cost-effective. The mode multiplexer/demultiplexer (MUX/DEMUX) consists of cascaded mode-selective couplers (MSCs), which are designed and fabricated by tapering the proposed FMF with single-mode fiber (SMF). The mode MUX and DEMUX achieve very low modal crosstalk not only for the multiplexing/demultiplexing but also for the coupling to/from the FMF. Based on the fabricated FMF and mode MUX/DEMUX, we successfully demonstrate the first simultaneous 4-modes (LP 01 , LP 11 , LP 21 & LP 31 ) 10-km FMF transmission with 10-Gb/s intensity modulation and MIMO-free direct detection (IM/DD). The modal crosstalk of the whole transmission link is successfully suppressed to less than -16.5 dB. The experimental results indicate that FMF with simple step-index structure supporting 4 weakly-coupled modes is feasible.

What can the past of pay-for-performance tell us about the future of Value-Based Purchasing in Medicare?

PubMed

Ryan, Andrew M; Damberg, Cheryl L

2013-06-01

The Medicare program has implemented pay-for-performance (P4P), or Value-Based Purchasing, for inpatient care and for Medicare Advantage plans, and plans to implement a program for physicians in 2015. In this paper, we review evidence on the effectiveness of P4P and identify design criteria deemed to be best practice in P4P. We then assess the extent to which Medicare's existing and planned Value-Based Purchasing programs align with these best practices. Of the seven identified best practices in P4P program design, the Hospital Value-Based Purchasing program is strongly aligned with two of the best practices, moderately aligned with three, weakly aligned with one, and has unclear alignment with one best practice. The Physician Value-Based Purchasing Modifier is strongly aligned with two of the best practices, moderately aligned with one, weakly aligned with three, and has unclear alignment with one of the best practices. The Medicare Advantage Quality Bonus Program is strongly aligned with four of the best practices, moderately aligned with two, and weakly aligned with one of the best practices. We identify enduring gaps in P4P literature as it relates to Medicare's plans for Value-Based Purchasing and discuss important issues in the future of these implementations in Medicare. Copyright © 2013 Elsevier Inc. All rights reserved.

Complete Calibration of the Color-Redshift Relation (C3R2): A Critical Foundation for Weak Lensing Cosmology with Euclid and WFIRST

NASA Astrophysics Data System (ADS)

Masters, Daniel C.; Stern, Daniel; Cohen, Judy; Capak, Peter

2018-01-01

A primary objective of both WFIRST and Euclid is to provide a 3D map of the distribution of matter across a significant fraction of the universe from the weak lensing shear field. Doing so will require accurate redshifts to the billions of galaxies that comprise the weak lensing samples of these surveys; achieving the required accuracy is a “tall pole” challenge for both missions. Here we present the ongoing Complete Calibration of the Color-Redshift Relation (C3R2) survey, designed specifically to calibrate the empirical galaxy color-redshift relation to Euclid depth. C3R2 is an ambitious Keck spectroscopy program, with a survey design based on a machine learning technique that allows us to optimally select the most important galaxies to sample the full range of galaxy colors. C3R2 is a multi-center program with time from all the primary Keck partners (Caltech, UC, Hawaii, and NASA), with a total of 34.5 Keck nights allocated to this project. Data Release 1, including 1283 high-confidence spectroscopic redshifts, is published as Masters, Stern, Cohen, Capak, et al. (2017), and we are currently completing Data Release 2, which will include >2000 additional high-confidence spectroscopic redshifts (Masters et al., in prep.). We will discuss current results and prospects for the survey going forward.

A knowledge-based system with learning for computer communication network design

NASA Technical Reports Server (NTRS)

Pierre, Samuel; Hoang, Hai Hoc; Tropper-Hausen, Evelyne

1990-01-01

Computer communication network design is well-known as complex and hard. For that reason, the most effective methods used to solve it are heuristic. Weaknesses of these techniques are listed and a new approach based on artificial intelligence for solving this problem is presented. This approach is particularly recommended for large packet switched communication networks, in the sense that it permits a high degree of reliability and offers a very flexible environment dealing with many relevant design parameters such as link cost, link capacity, and message delay.

Preliminary design work on a DSN VLBI correlator. [Deep Space Network

NASA Technical Reports Server (NTRS)

Lushbaugh, W. A.; Layland, J. W.

1978-01-01

The Deep Space Network is in the process of fielding high-density digital instrumentation recorders for support of the Pioneer Venus 1978 entry experiment and other related tasks. It has long been obvious that these recorders would also serve well as the recording medium for very long base interferometry (VLBI) experiments with relatively weak radio sources, provided that a suitable correlation processor for these tape recordings could be established. The overall design and current status of a VLBI correlator designed to mate with these tape recorders are described.

Research: increasing value, reducing waste 2

PubMed Central

Ioannidis, John P A; Greenland, Sander; Hlatky, Mark A; Khoury, Muin J; Macleod, Malcolm R; Moher, David; Schulz, Kenneth F; Tibshirani, Robert

2015-01-01

Correctable weaknesses in the design, conduct, and analysis of biomedical and public health research studies can produce misleading results and waste valuable resources. Small effects can be difficult to distinguish from bias introduced by study design and analyses. An absence of detailed written protocols and poor documentation of research is common. Information obtained might not be useful or important, and statistical precision or power is often too low or used in a misleading way. Insufficient consideration might be given to both previous and continuing studies. Arbitrary choice of analyses and an overemphasis on random extremes might affect the reported findings. Several problems relate to the research workforce, including failure to involve experienced statisticians and methodologists, failure to train clinical researchers and laboratory scientists in research methods and design, and the involvement of stakeholders with conflicts of interest. Inadequate emphasis is placed on recording of research decisions and on reproducibility of research. Finally, reward systems incentivise quantity more than quality, and novelty more than reliability. We propose potential solutions for these problems, including improvements in protocols and documentation, consideration of evidence from studies in progress, standardisation of research efforts, optimisation and training of an experienced and non-conflicted scientific workforce, and reconsideration of scientific reward systems. PMID:24411645

A Community-Based Intervention to Prevent Obesity Beginning at Birth among American Indian Children: Study Design and Rationale for the PTOTS study

PubMed Central

Karanja, Njeri; Aickin, Mikel; Lutz, Tam; Mist, Scott; Jobe, Jared B.; Maupomé, Gerardo; Ritenbaugh, Cheryl

2012-01-01

Eating and physical activity behaviors associated with adult obesity have early antecedents, yet few studies have focused on obesity prevention interventions targeting very young children. Efforts to prevent obesity beginning at birth seem particularly important in populations at risk for early-onset obesity. National estimates indicate that American Indian (AI) children have higher rates of overweight and obesity than children of other races/ethnicities. The Prevention of Toddler Obesity and Teeth Health Study (PTOTS) is a community-partnered randomized controlled trial designed to prevent obesity beginning at birth in AI children. PTOTS was developed to test the effectiveness of a multi-component intervention designed to: promote breastfeeding, reduce sugar-sweetened beverage consumption, appropriately time the introduction of healthy solid foods, and counsel parents to reduce sedentary lifestyles in their children. A birth cohort of 577 children from five AI tribes is randomized by tribe to either the intervention (three tribes) or the comparison condition (two tribes). The strengths and weaknesses of PTOTS include a focus on a critical growth phase, placement in the community, and intervention at many levels, using a variety of approaches. PMID:23001689

Comparison of Home Retrofit Programs in Wisconsin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cunningham, Kerrie; Hannigan, Eileen

2013-03-01

To explore ways to reduce customer barriers and increase home retrofit completions, several different existing home retrofit models have been implemented in the state of Wisconsin. This study compared these programs' performance in terms of savings per home and program cost per home to assess the relative cost-effectiveness of each program design. However, given the many variations in these different programs, it is difficult to establish a fair comparison based on only a small number of metrics. Therefore, the overall purpose of the study is to document these programs' performance in a case study approach to look at general patternsmore » of these metrics and other variables within the context of each program. This information can be used by energy efficiency program administrators and implementers to inform home retrofit program design. Six different program designs offered in Wisconsin for single-family energy efficiency improvements were included in the study. For each program, the research team provided information about the programs' approach and goals, characteristics, achievements and performance. The program models were then compared with performance results-program cost and energy savings-to help understand the overall strengths and weaknesses or challenges of each model.« less

Comparison of Home Retrofit Programs in Wisconsin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cunningham, K.; Hannigan, E.

2013-03-01

To explore ways to reduce customer barriers and increase home retrofit completions, several different existing home retrofit models have been implemented in the state of Wisconsin. This study compared these programs' performance in terms of savings per home and program cost per home to assess the relative cost-effectiveness of each program design. However, given the many variations in these different programs, it is difficult to establish a fair comparison based on only a small number of metrics. Therefore, the overall purpose of the study is to document these programs' performance in a case study approach to look at general patternsmore » of these metrics and other variables within the context of each program. This information can be used by energy efficiency program administrators and implementers to inform home retrofit program design. Six different program designs offered in Wisconsin for single-family energy efficiency improvements were included in the study. For each program, the research team provided information about the programs' approach and goals, characteristics, achievements and performance. The program models were then compared with performance results -- program cost and energy savings -- to help understand the overall strengths and weaknesses or challenges of each model.« less

A weak pattern random creation and scoring method for lithography process tuning

NASA Astrophysics Data System (ADS)

Zhang, Meili; Deng, Guogui; Wang, Mudan; Yu, Shirui; Hu, Xinyi; Du, Chunshan; Wan, Qijian; Liu, Zhengfang; Gao, Gensheng; Kabeel, Aliaa; Madkour, Kareem; ElManhawy, Wael; Kwan, Joe

2018-03-01

As the IC technology node moves forward, critical dimension becomes smaller and smaller, which brings huge challenge to IC manufacturing. Lithography is one of the most important steps during the whole manufacturing process and litho hotspots become a big source of yield detractors. Thus tuning lithographic recipes to cover a big range of litho hotspots is very essential to yield enhancing. During early technology developing stage, foundries only have limited customer layout data for recipe tuning. So collecting enough patterns is significant for process optimization. After accumulating enough patterns, a general way to treat them is not precise and applicable. Instead, an approach to scoring these patterns could provide a priority and reference to address different patterns more effectively. For example, the weakest group of patterns could be applied the most limited specs to ensure process robustness. This paper presents a new method of creation of real design alike patterns of multiple layers based on design rules using Layout Schema Generator (LSG) utility and a pattern scoring flow using Litho-friendly Design (LFD) and Pattern Matching. Through LSG, plenty of new unknown patterns could be created for further exploration. Then, litho simulation through LFD and topological matches by using Pattern Matching is applied on the output patterns of LSG. Finally, lithographical severity, printability properties and topological distribution of every pattern are collected. After a statistical analysis of pattern data, every pattern is given a relative score representing the pattern's yield detracting level. By sorting the output pattern score tables, weak patterns could be filtered out for further research and process tuning. This pattern generation and scoring flow is demonstrated on 28nm logic technology node. A weak pattern library is created and scored to help improve recipe coverage of litho hotspots and enhance the reliability of process.

Training production of lexical stress in typically developing children using orthographically biased stimuli and principles of motor learning.

PubMed

van Rees, Lauren J; Ballard, Kirrie J; McCabe, Patricia; Macdonald-D'Silva, Anita G; Arciuli, Joanne

2012-08-01

Impaired lexical stress production characterizes multiple pediatric speech disorders. Effective remediation strategies are not available, and little is known about the normal process of learning to assign and produce lexical stress. This study examined whether typically developing (TD) children can be trained to produce lexical stress on bisyllabic pseudowords that are orthographically biased to a strong-weak or weak-strong pattern (e.g., MAMbey or beDOON), in combination with the principles of motor learning (PML). Fourteen TD children ages 5;0 (years;months) to 13;0 were randomly assigned to a training or control group using concealed allocation within blocks. A pre- to posttraining group design was used to examine the acquisition, retention, and generalization of lexical stress production. The training group learned to produce appropriate lexical stress for the pseudowords with strong maintenance and generalization to related untrained stimuli. Accuracy of stress production did not change in the control group. TD children can learn to produce lexical stress patterns for orthographically biased pseudowords via explicit training methods. Findings have relevance for the study of languages other than English and for a range of prosodic disorders.

Combining large number of weak biomarkers based on AUC.

PubMed

Yan, Li; Tian, Lili; Liu, Song

2015-12-20

Combining multiple biomarkers to improve diagnosis and/or prognosis accuracy is a common practice in clinical medicine. Both parametric and non-parametric methods have been developed for finding the optimal linear combination of biomarkers to maximize the area under the receiver operating characteristic curve (AUC), primarily focusing on the setting with a small number of well-defined biomarkers. This problem becomes more challenging when the number of observations is not order of magnitude greater than the number of variables, especially when the involved biomarkers are relatively weak. Such settings are not uncommon in certain applied fields. The first aim of this paper is to empirically evaluate the performance of existing linear combination methods under such settings. The second aim is to propose a new combination method, namely, the pairwise approach, to maximize AUC. Our simulation studies demonstrated that the performance of several existing methods can become unsatisfactory as the number of markers becomes large, while the newly proposed pairwise method performs reasonably well. Furthermore, we apply all the combination methods to real datasets used for the development and validation of MammaPrint. The implication of our study for the design of optimal linear combination methods is discussed. Copyright © 2015 John Wiley & Sons, Ltd.

Combining large number of weak biomarkers based on AUC

PubMed Central

Yan, Li; Tian, Lili; Liu, Song

2018-01-01

Combining multiple biomarkers to improve diagnosis and/or prognosis accuracy is a common practice in clinical medicine. Both parametric and non-parametric methods have been developed for finding the optimal linear combination of biomarkers to maximize the area under the receiver operating characteristic curve (AUC), primarily focusing on the setting with a small number of well-defined biomarkers. This problem becomes more challenging when the number of observations is not order of magnitude greater than the number of variables, especially when the involved biomarkers are relatively weak. Such settings are not uncommon in certain applied fields. The first aim of this paper is to empirically evaluate the performance of existing linear combination methods under such settings. The second aim is to propose a new combination method, namely, the pairwise approach, to maximize AUC. Our simulation studies demonstrated that the performance of several existing methods can become unsatisfactory as the number of markers becomes large, while the newly proposed pairwise method performs reasonably well. Furthermore, we apply all the combination methods to real datasets used for the development and validation of MammaPrint. The implication of our study for the design of optimal linear combination methods is discussed. PMID:26227901

The role of decision analytic modeling in the health economic assessment of spinal intervention.

PubMed

Edwards, Natalie C; Skelly, Andrea C; Ziewacz, John E; Cahill, Kevin; McGirt, Matthew J

2014-10-15

Narrative review. To review the common tenets, strengths, and weaknesses of decision modeling for health economic assessment and to review the use of decision modeling in the spine literature to date. For the majority of spinal interventions, well-designed prospective, randomized, pragmatic cost-effectiveness studies that address the specific decision-in-need are lacking. Decision analytic modeling allows for the estimation of cost-effectiveness based on data available to date. Given the rising demands for proven value in spine care, the use of decision analytic modeling is rapidly increasing by clinicians and policy makers. This narrative review discusses the general components of decision analytic models, how decision analytic models are populated and the trade-offs entailed, makes recommendations for how users of spine intervention decision models might go about appraising the models, and presents an overview of published spine economic models. A proper, integrated, clinical, and economic critical appraisal is necessary in the evaluation of the strength of evidence provided by a modeling evaluation. As is the case with clinical research, all options for collecting health economic or value data are not without their limitations and flaws. There is substantial heterogeneity across the 20 spine intervention health economic modeling studies summarized with respect to study design, models used, reporting, and general quality. There is sparse evidence for populating spine intervention models. Results mostly showed that interventions were cost-effective based on $100,000/quality-adjusted life-year threshold. Spine care providers, as partners with their health economic colleagues, have unique clinical expertise and perspectives that are critical to interpret the strengths and weaknesses of health economic models. Health economic models must be critically appraised for both clinical validity and economic quality before altering health care policy, payment strategies, or patient care decisions. 4.

Re-examining overlap between tactile and visual motion responses within hMT+ and STS

PubMed Central

Jiang, Fang; Beauchamp, Michael S.; Fine, Ione

2015-01-01

Here we examine overlap between tactile and visual motion BOLD responses within the human MT+ complex. Although several studies have reported tactile responses overlapping with hMT+, many used group average analyses, leaving it unclear whether these responses were restricted to sub-regions of hMT+. Moreover, previous studies either employed a tactile task or passive stimulation, leaving it unclear whether or not tactile responses in hMT+ are simply the consequence of visual imagery. Here we carried out a replication of one of the classic papers finding tactile responses in hMT+ (Hagen et al. 2002). We mapped MT and MST in individual subjects using visual field localizers. We then examined responses to tactile motion on the arm, either presented passively or in the presence of a visual task performed at fixation designed to minimize visualization of the concurrent tactile stimulation. To our surprise, without a visual task, we found only weak tactile motion responses in MT (6% of voxels showing tactile responses) and MST (2% of voxels). With an unrelated visual task designed to withdraw attention from the tactile modality, responses in MST reduced to almost nothing (<1% regions). Consistent with previous results, we did observe tactile responses in STS regions superior and anterior to hMT+. Despite the lack of individual overlap, group averaged responses produced strong spurious overlap between tactile and visual motion responses within hMT+ that resembled those observed in previous studies. The weak nature of tactile responses in hMT+ (and their abolition by withdrawal of attention) suggests that hMT+ may not serve as a supramodal motion processing module. PMID:26123373

Methodological issues in negative symptom trials.

PubMed

Marder, Stephen R; Daniel, David G; Alphs, Larry; Awad, A George; Keefe, Richard S E

2011-03-01

Individuals from academia, the pharmaceutical industry, and the US Food and Drug Administration used a workshop format to discuss important methodological issues in the design of trials of pharmacological agents for improving negative symptoms in schizophrenia. The issues addressed included the need for a coprimary functional measure for registration trials; the characteristics of individuals who should enter negative symptom trials; the optimal duration for a proof-of-concept or registration trial; the optimal design of a study of a broad-spectrum agent that treats both positive and negative symptoms or a co-medication that is added to an antipsychotic; the relative strengths and weaknesses of available instruments for measuring negative symptoms; the definition of clinically meaningful improvement for these trials; and whether drugs can be approved for a subdomain of negative symptoms.

Methodological Issues in Negative Symptom Trials

PubMed Central

Marder, Stephen R.; Daniel, David G.; Alphs, Larry; Awad, A. George; Keefe, Richard S. E.

2011-01-01

Individuals from academia, the pharmaceutical industry, and the US Food and Drug Administration used a workshop format to discuss important methodological issues in the design of trials of pharmacological agents for improving negative symptoms in schizophrenia. The issues addressed included the need for a coprimary functional measure for registration trials; the characteristics of individuals who should enter negative symptom trials; the optimal duration for a proof-of-concept or registration trial; the optimal design of a study of a broad-spectrum agent that treats both positive and negative symptoms or a co-medication that is added to an antipsychotic; the relative strengths and weaknesses of available instruments for measuring negative symptoms; the definition of clinically meaningful improvement for these trials; and whether drugs can be approved for a subdomain of negative symptoms. PMID:21270473

Enhanced collective focusing of intense neutralized ion beam pulses in the presence of weak solenoidal magnetic fields

DOE PAGES

Dorf, Mikhail A.; Davidson, Ronald C.; Kaganovich, Igor D.; ...

2012-05-31

In this study, the design of ion drivers for warm dense matter and high energy density physics applications and heavy ion fusion involves transverse focusing and longitudinal compression of intense ion beams to a small spot size on the target. To facilitate the process, the compression occurs in a long drift section filled with a dense background plasma, which neutralizes the intense beam self-fields. Typically, the ion bunch charge is better neutralized than its current, and as a result a net self-pinching (magnetic) force is produced. The self-pinching effect is of particular practical importance, and is used in various ionmore » driver designs in order to control the transverse beam envelope. In the present work we demonstrate that this radial self-focusing force can be significantly enhanced if a weak (B~100 G) solenoidal magnetic field is applied inside the neutralized drift section, thus allowing for substantially improved transport. It is shown that in contrast to magnetic self-pinching, the enhanced collective self-focusing has a radial electric field component and occurs as a result of the overcompensation of the beam charge by plasmaelectrons, whereas the beam current becomes well-neutralized. As the beam leaves the neutralizing drift section, additional transverse focusing can be applied. For instance, in the neutralized drift compression experiments (NDCX) a strong (several Tesla) final focus solenoid is used for this purpose. In the present analysis we propose that the tight final focus in the NDCX experiments may possibly be achieved by using a much weaker (few hundred Gauss) magnetic lens, provided the ion beam carries an equal amount of co-moving neutralizing electrons from the preceding drift section into the lens. In this case the enhanced focusing is provided by the collective electrondynamics strongly affected by a weak applied magnetic field.« less

Consume, Modify, Share (CMS): The Interplay between Individual Decisions and Structural Network Properties in the Diffusion of Information

PubMed Central

Koren, Hila; Kaminer, Ido

2016-01-01

Widely used information diffusion models such as Independent Cascade Model, Susceptible Infected Recovered (SIR) and others fail to acknowledge that information is constantly subject to modification. Some aspects of information diffusion are best explained by network structural characteristics while in some cases strong influence comes from individual decisions. We introduce reinvention, the ability to modify information, as an individual level decision that affects the diffusion process as a whole. Based on a combination of constructs from the Diffusion of Innovations and the Critical Mass Theories, the present study advances the CMS (consume, modify, share) model which accounts for the interplay between network structure and human behavior and interactions. The model's building blocks include processes leading up to and following the formation of a critical mass of information adopters and disseminators. We examine the formation of an inflection point, information reach, sustainability of the diffusion process and collective value creation. The CMS model is tested on two directed networks and one undirected network, assuming weak or strong ties and applying constant and relative modification schemes. While all three networks are designed for disseminating new knowledge they differ in structural properties. Our findings suggest that modification enhances the diffusion of information in networks that support undirected connections and carries the biggest effect when information is shared via weak ties. Rogers' diffusion model and traditional information contagion models are fine tuned. Our results show that modifications not only contribute to a sustainable diffusion process, but also aid information in reaching remote areas of the network. The results point to the importance of cultivating weak ties, allowing reciprocal interaction among nodes and supporting the modification of information in promoting diffusion processes. These results have theoretical and practical implications for designing networks aimed at accelerating the creation and diffusion of information. PMID:27798636

Consume, Modify, Share (CMS): The Interplay between Individual Decisions and Structural Network Properties in the Diffusion of Information.

PubMed

Koren, Hila; Kaminer, Ido; Raban, Daphne Ruth

2016-01-01

Widely used information diffusion models such as Independent Cascade Model, Susceptible Infected Recovered (SIR) and others fail to acknowledge that information is constantly subject to modification. Some aspects of information diffusion are best explained by network structural characteristics while in some cases strong influence comes from individual decisions. We introduce reinvention, the ability to modify information, as an individual level decision that affects the diffusion process as a whole. Based on a combination of constructs from the Diffusion of Innovations and the Critical Mass Theories, the present study advances the CMS (consume, modify, share) model which accounts for the interplay between network structure and human behavior and interactions. The model's building blocks include processes leading up to and following the formation of a critical mass of information adopters and disseminators. We examine the formation of an inflection point, information reach, sustainability of the diffusion process and collective value creation. The CMS model is tested on two directed networks and one undirected network, assuming weak or strong ties and applying constant and relative modification schemes. While all three networks are designed for disseminating new knowledge they differ in structural properties. Our findings suggest that modification enhances the diffusion of information in networks that support undirected connections and carries the biggest effect when information is shared via weak ties. Rogers' diffusion model and traditional information contagion models are fine tuned. Our results show that modifications not only contribute to a sustainable diffusion process, but also aid information in reaching remote areas of the network. The results point to the importance of cultivating weak ties, allowing reciprocal interaction among nodes and supporting the modification of information in promoting diffusion processes. These results have theoretical and practical implications for designing networks aimed at accelerating the creation and diffusion of information.

Nonconvex Sparse Logistic Regression With Weakly Convex Regularization

NASA Astrophysics Data System (ADS)

Shen, Xinyue; Gu, Yuantao

2018-06-01

In this work we propose to fit a sparse logistic regression model by a weakly convex regularized nonconvex optimization problem. The idea is based on the finding that a weakly convex function as an approximation of the $\\ell_0$ pseudo norm is able to better induce sparsity than the commonly used $\\ell_1$ norm. For a class of weakly convex sparsity inducing functions, we prove the nonconvexity of the corresponding sparse logistic regression problem, and study its local optimality conditions and the choice of the regularization parameter to exclude trivial solutions. Despite the nonconvexity, a method based on proximal gradient descent is used to solve the general weakly convex sparse logistic regression, and its convergence behavior is studied theoretically. Then the general framework is applied to a specific weakly convex function, and a necessary and sufficient local optimality condition is provided. The solution method is instantiated in this case as an iterative firm-shrinkage algorithm, and its effectiveness is demonstrated in numerical experiments by both randomly generated and real datasets.

Design of Bcl-2 and Bcl-xL Inhibitors with Subnanomolar Binding Affinities Based upon a New Scaffold

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Haibin; Chen, Jianfang; Meagher, Jennifer L.

Employing a structure-based strategy, we have designed a new class of potent small-molecule inhibitors of the anti-apoptotic proteins Bcl-2 and Bcl-xL. An initial lead compound with a new scaffold was designed based upon the crystal structure of Bcl-xL and U.S. Food and Drug Administration (FDA) approved drugs and was found to have an affinity of 100 {micro}M for both Bcl-2 and Bcl-xL. Linking this weak lead to another weak-affinity fragment derived from Abbott's ABT-737 led to an improvement of the binding affinity by a factor of >10,000. Further optimization ultimately yielded compounds with subnanomolar binding affinities for both Bcl-2 andmore » Bcl-xL and potent cellular activity. The best compound (21) binds to Bcl-xL and Bcl-2 with K{sub i} < 1 nM, inhibits cell growth in the H146 and H1417 small-cell lung cancer cell lines with IC{sub 50} values of 60-90 nM, and induces robust cell death in the H146 cancer cell line at 30-100 nM.« less

Using Qualitative Comparative Analysis (QCA) of Key Informant Interviews in Health Services Research: Enhancing a Study of Adjuvant Therapy Use in Breast Cancer Care

PubMed Central

McAlearney, Ann Scheck; Walker, Daniel; Moss, Alexandra DeNardis; Bickell, Nina A.

2015-01-01

Background Qualitative Comparative Analysis (QCA) is a methodology created to address causal complexity in social sciences research by preserving the objectivity of quantitative data analysis without losing detail inherent in qualitative research. However, its use in health services research (HSR) is limited, and questions remain about its application in this context. Objective To explore the strengths and weaknesses of using QCA for HSR. Research Design Using data from semi-structured interviews conducted as part of a multiple case study about adjuvant treatment underuse among underserved breast cancer patients, findings were compared using qualitative approaches with and without QCA to identify strengths, challenges, and opportunities presented by QCA. Subjects Ninety administrative and clinical key informants interviewed across ten NYC area safety net hospitals. Measures Transcribed interviews were coded by three investigators using an iterative and interactive approach. Codes were calibrated for QCA, as well as examined using qualitative analysis without QCA. Results Relative to traditional qualitative analysis, QCA strengths include: (1) addressing causal complexity, (2) results presentation as pathways as opposed to a list, (3) identification of necessary conditions, (4) the option of fuzzy-set calibrations, and (5) QCA-specific parameters of fit that allow researchers to compare outcome pathways. Weaknesses include: (1) few guidelines and examples exist for calibrating interview data, (2) not designed to create predictive models, and (3) unidirectionality. Conclusions Through its presentation of results as pathways, QCA can highlight factors most important for production of an outcome. This strength can yield unique benefits for HSR not available through other methods. PMID:26908085

Validating Actigraphy as a Measure of Sleep for Preschool Children

PubMed Central

Bélanger, Marie-Ève; Bernier, Annie; Paquet, Jean; Simard, Valérie; Carrier, Julie

2013-01-01

Study Objectives: The algorithms used to derive sleep variables from actigraphy were developed with adults. Because children change position during sleep more often than adults, algorithms may detect wakefulness when the child is actually sleeping (false negative). This study compares the validity of three algorithms for detecting sleep with actigraphy by comparing them to PSG in preschoolers. The putative influence of device location (wrist or ankle) is also examined. Methods: Twelve children aged 2 to 5 years simultaneously wore an actigraph on an ankle and a wrist (Actiwatch-L, Mini-Mitter/Respironics) during a night of PSG recording at home. Three algorithms were tested: one recommended for adults and two designed to decrease false negative detection of sleep in children. Results: Actigraphy generally showed good sensitivity (> 95%; PSG sleep detection) but low specificity (± 50%; PSG wake detection). Intraclass correlations between PSG and actigraphy variables were strong (> 0.80) for sleep latency, sleep duration, and sleep efficiency, but weak for number of awakenings (< 0.40). The two algorithms designed for children enhanced the validity of actigraphy in preschoolers and increased the proportion of actigraphy-scored wake epochs scored that were also PSG-identified as wake. Sleep variables derived from the ankle and wrist were not statistically different. Conclusion: Despite the weak detection of wakefulness, Acti-watch-L appears to be a useful instrument for assessing sleep in preschoolers when used with an adapted algorithm. Citation: Bélanger M; Bernier A; Paquet J; Simard V; Julie Carrier J. Validating actigraphy as a measure of sleep for pre-school children. J Clin Sleep Med 2013;9(7):701-706. PMID:23853565

Guidelines for pre-clinical animal and cellular models of MuSK-myasthenia gravis.

PubMed

Phillips, W D; Christadoss, P; Losen, M; Punga, A R; Shigemoto, K; Verschuuren, J; Vincent, A

2015-08-01

Muscle-specific tyrosine kinase (MuSK) autoantibodies are the hallmark of a form of myasthenia gravis (MG) that can challenge the neurologist and the experimentalist. The clinical disease can be difficult to treat effectively. MuSK autoantibodies affect the neuromuscular junction in several ways. When added to muscle cells in culture, MuSK antibodies disperse acetylcholine receptor clusters. Experimental animals actively immunized with MuSK develop MuSK autoantibodies and muscle weakness. Weakness is associated with reduced postsynaptic acetylcholine receptor numbers, reduced amplitudes of miniature endplate potentials and endplate potentials, and failure of neuromuscular transmission. Similar impairments have been found in mice injected with IgG from MG patients positive for MuSK autoantibody (MuSK-MG). The active and passive models have begun to reveal the mechanisms by which MuSK antibodies disrupt synaptic function at the neuromuscular junction, and should be valuable in developing therapies for MuSK-MG. However, translation into new and improved treatments for patients requires procedures that are not too cumbersome but suitable for examining different aspects of MuSK function and the effects of potential therapies. Study design, conduct and analysis should be carefully considered and transparently reported. Here we review what has been learnt from animal and culture models of MuSK-MG, and offer guidelines for experimental design and conduct of studies, including sample size determination, randomization, outcome parameters and precautions for objective data analysis. These principles may also be relevant to the increasing number of other antibody-mediated diseases that are now recognized. Copyright © 2014 Elsevier Inc. All rights reserved.

Revisiting Weak Emission-line Quasars with a Simple Approach to Deduce their Nature and the Tracers of X-ray Weakness

NASA Astrophysics Data System (ADS)

Ni, Qingling

2018-01-01

We present an X-ray and multi-wavelength study of 17 “bridge” weak emission-line quasars (WLQs) and 16 “extreme” WLQs naturally divided by their C IV rest equivalent widths (REWs), which constitute our clean WLQ sample together. New Chandra 3.1-4.8 ks observations were obtained for 14 objects while the other 19 have archival X-ray observations. 4 of the 17 bridge WLQs appear to be X-ray weak, while 9 of the 16 extreme WLQs appear to be X-ray weak. The X-ray weak fraction in the bridge sample (23.5%) is lower than in the extreme sample(56.3%), indicating the fraction of X-ray weak objects along with rising C IV REWs.X-ray stacking analysis is performed for the X-ray weak WLQs in the clean sample. We measured a relatively hard (Γeff=1.37) effective power-law photon index for a stack of the X-ray weak subsample, suggesting X-ray absorption due to shielding material inside the broad emission-line region (BELR). We proposed a geometrically and optically thick inner accretion disk as the natural shield, which could also explain the behavior of the X-ray weak fraction along with C IV REW.Futhermore, we ran Peto-Prentice tests to assess if the distributions of optical-UV spectral properties are different between X-ray weak WLQs and X-ray normal WLQs. We also examined correlations between △αOX and optical-UV spectral properties. The C IV REW, C IV blueshift, C IV FWHM, REWs of the Si IV, λ1900, Fe II, and Mg II emission features, and the relative SDSS color △(g - i) are examined in our study. △(g - i) turned out to be the most effective tracer of X-ray weakness.

Composite Ceramic Superconducting Wires for Electric Motor Applications

DTIC Science & Technology

1989-10-10

on several approaches to overcome weak link behavio. by melt texturing. Design was completed for the first generation HTSC motor , a drum DC homopolar ...29 3.2 Homopolar Motor ....................................................... 29 3.3 Testing...35 3.3.3 Homopolar Tests............................................. 35 3.4 Other Motors

Lotus 123 as a Gradebook: A Means of Increasing Teacher Productivity.

ERIC Educational Resources Information Center

Smith, Karen L.

1988-01-01

Examines the application of the spreadsheet program Lotus 1-2-3 to design a computerized gradebook that saves time in assessing students' strengths and weaknesses in a proficiency-oriented foreign language classroom. Sample entries are shown in text and Appendices. (Author/LMO)

Desktop Publishing in Education.

ERIC Educational Resources Information Center

Hall, Wendy; Layman, J.

1989-01-01

Discusses the state of desktop publishing (DTP) in education today and describes the weaknesses of the systems available for use in the classroom. Highlights include document design and layout; text composition; graphics; word processing capabilities; a comparison of commercial and educational DTP packages; and skills required for DTP. (four…

A Critique of the Research on Learning Styles.

ERIC Educational Resources Information Center

Curry, Lynn

1990-01-01

Learning styles advocates claim long-term improvements in four aspects of teaching and learning: curriculum design, instructional methods, assessment, and student guidance. The application of learning style theory encompasses three pervasive problems: confusion in definitions, weakness in measurement reliability and validity, and identification of…

Evaluating the performance of parallel subsurface simulators: An illustrative example with PFLOTRAN

PubMed Central

Hammond, G E; Lichtner, P C; Mills, R T

2014-01-01

[1] To better inform the subsurface scientist on the expected performance of parallel simulators, this work investigates performance of the reactive multiphase flow and multicomponent biogeochemical transport code PFLOTRAN as it is applied to several realistic modeling scenarios run on the Jaguar supercomputer. After a brief introduction to the code's parallel layout and code design, PFLOTRAN's parallel performance (measured through strong and weak scalability analyses) is evaluated in the context of conceptual model layout, software and algorithmic design, and known hardware limitations. PFLOTRAN scales well (with regard to strong scaling) for three realistic problem scenarios: (1) in situ leaching of copper from a mineral ore deposit within a 5-spot flow regime, (2) transient flow and solute transport within a regional doublet, and (3) a real-world problem involving uranium surface complexation within a heterogeneous and extremely dynamic variably saturated flow field. Weak scalability is discussed in detail for the regional doublet problem, and several difficulties with its interpretation are noted. PMID:25506097

Evaluating the performance of parallel subsurface simulators: An illustrative example with PFLOTRAN.

PubMed

Hammond, G E; Lichtner, P C; Mills, R T

2014-01-01

[1] To better inform the subsurface scientist on the expected performance of parallel simulators, this work investigates performance of the reactive multiphase flow and multicomponent biogeochemical transport code PFLOTRAN as it is applied to several realistic modeling scenarios run on the Jaguar supercomputer. After a brief introduction to the code's parallel layout and code design, PFLOTRAN's parallel performance (measured through strong and weak scalability analyses) is evaluated in the context of conceptual model layout, software and algorithmic design, and known hardware limitations. PFLOTRAN scales well (with regard to strong scaling) for three realistic problem scenarios: (1) in situ leaching of copper from a mineral ore deposit within a 5-spot flow regime, (2) transient flow and solute transport within a regional doublet, and (3) a real-world problem involving uranium surface complexation within a heterogeneous and extremely dynamic variably saturated flow field. Weak scalability is discussed in detail for the regional doublet problem, and several difficulties with its interpretation are noted.

The KP Approximation Under a Weak Coriolis Forcing

NASA Astrophysics Data System (ADS)

Melinand, Benjamin

2018-02-01

In this paper, we study the asymptotic behavior of weakly transverse water-waves under a weak Coriolis forcing in the long wave regime. We derive the Boussinesq-Coriolis equations in this setting and we provide a rigorous justification of this model. Then, from these equations, we derive two other asymptotic models. When the Coriolis forcing is weak, we fully justify the rotation-modified Kadomtsev-Petviashvili equation (also called Grimshaw-Melville equation). When the Coriolis forcing is very weak, we rigorously justify the Kadomtsev-Petviashvili equation. This work provides the first mathematical justification of the KP approximation under a Coriolis forcing.

Experimental joint weak measurement on a photon pair as a probe of Hardy's paradox.

PubMed

Lundeen, J S; Steinberg, A M

2009-01-16

It has been proposed that the ability to perform joint weak measurements on postselected systems would allow us to study quantum paradoxes. These measurements can investigate the history of those particles that contribute to the paradoxical outcome. Here we experimentally perform weak measurements of joint (i.e., nonlocal) observables. In an implementation of Hardy's paradox, we weakly measure the locations of two photons, the subject of the conflicting statements behind the paradox. Remarkably, the resulting weak probabilities verify all of these statements but, at the same time, resolve the paradox.

Passive Participle Marking by African American English–Speaking Children Reared in Poverty

PubMed Central

Pruitt, Sonja L.; Oetting, Janna B.; Hegarty, Michael

2012-01-01

Purpose In this study, the authors examined the linguistic profile of African American English (AAE)-speaking children reared in poverty by focusing on their marking of passive participles and by comparing the results with the authors’ previous study of homophonous forms of past tense (S. Pruitt & J. Oetting, 2009). Method The data were from 45 five- to six-year-olds who spoke AAE and who participated in the authors’ earlier study. Fifteen were classified as low-income (LSES); the others were classified as middle-income and served as either age- or language-matched controls. The data came from a probe that was designed by S. M. Redmond (2003), but it was modified to examine the morphological and phonological characteristics of AAE. Results Participle marking by all 3 groups was influenced by AAE phonology, but the LSES children marked the participles at lower rates than the controls. The LSES children’s rates of participle marking were also lower than their rates of marking for homophonous forms of past tense. Unlike the children’s rates of past-tense marking, their rates of participle marking were correlated to their vocabulary test scores. Conclusions AAE-speaking children reared in poverty present weaknesses in aspects of grammatical morphology that are related to their vocabulary weaknesses. PMID:20966390

Caloric compensation for sugar-sweetened beverages in meals: A population-based study in Brazil.

PubMed

Gombi-Vaca, Maria Fernanda; Sichieri, Rosely; Verly, Eliseu

2016-03-01

Sugar-sweetened beverage (SSB) consumption can cause positive energy balance, therefore leading to weight gain. A plausible biological mechanism to explain this association is through weak caloric compensation for liquid calories. However, there is an ongoing debate surrounding SSB calorie compensation. The body of evidence comes from a diversity of study designs and highly controlled settings assessing food and beverage intake. Our study aimed to test for caloric compensation of SSB in the free-living setting of daily meals. We analyzed two food records of participants (age 10 years or older) from the 2008-2009 National Dietary Survey (Brazil, N = 34,003). We used multilevel analyses to estimate the within-subject effects of SSB on food intake. Sugar-sweetened beverage calories were not compensated for when comparing daily energy intake over two days for each individual. When comparing meals, we found 42% of caloric compensation for breakfast, no caloric compensation for lunch and zero to 22% of caloric compensation for dinner, differing by household per capita income. In conclusion, SSB consumption contributed to higher energy intake due to weak caloric compensation. Discouraging the intake of SSB especially during lunch and dinner may help reduce excessive energy intake and lead to better weight management. Copyright © 2015 Elsevier Ltd. All rights reserved.

Passive participle marking by African American English-speaking children reared in poverty.

PubMed

Pruitt, Sonja L; Oetting, Janna B; Hegarty, Michael

2011-04-01

In this study, the authors examined the linguistic profile of African American English (AAE)-speaking children reared in poverty by focusing on their marking of passive participles and by comparing the results with the authors' previous study of homophonous forms of past tense (S. Pruitt & J. Oetting, 2009). The data were from 45 five- to six-year-olds who spoke AAE and who participated in the authors' earlier study. Fifteen were classified as low-income (LSES); the others were classified as middle-income and served as either age- or language-matched controls. The data came from a probe that was designed by S. M. Redmond (2003), but it was modified to examine the morphological and phonological characteristics of AAE. Participle marking by all 3 groups was influenced by AAE phonology, but the LSES children marked the participles at lower rates than the controls. The LSES children's rates of participle marking were also lower than their rates of marking for homophonous forms of past tense. Unlike the children's rates of past-tense marking, their rates of participle marking were correlated to their vocabulary test scores. AAE-speaking children reared in poverty present weaknesses in aspects of grammatical morphology that are related to their vocabulary weaknesses.

Language, reading, and math learning profiles in an epidemiological sample of school age children.

PubMed

Archibald, Lisa M D; Oram Cardy, Janis; Joanisse, Marc F; Ansari, Daniel

2013-01-01

Dyscalculia, dyslexia, and specific language impairment (SLI) are relatively specific developmental learning disabilities in math, reading, and oral language, respectively, that occur in the context of average intellectual capacity and adequate environmental opportunities. Past research has been dominated by studies focused on single impairments despite the widespread recognition that overlapping and comorbid deficits are common. The present study took an epidemiological approach to study the learning profiles of a large school age sample in language, reading, and math. Both general learning profiles reflecting good or poor performance across measures and specific learning profiles involving either weak language, weak reading, weak math, or weak math and reading were observed. These latter four profiles characterized 70% of children with some evidence of a learning disability. Low scores in phonological short-term memory characterized clusters with a language-based weakness whereas low or variable phonological awareness was associated with the reading (but not language-based) weaknesses. The low math only group did not show these phonological deficits. These findings may suggest different etiologies for language-based deficits in language, reading, and math, reading-related impairments in reading and math, and isolated math disabilities.

Language, Reading, and Math Learning Profiles in an Epidemiological Sample of School Age Children

PubMed Central

Archibald, Lisa M. D.; Oram Cardy, Janis; Joanisse, Marc F.; Ansari, Daniel

2013-01-01

Dyscalculia, dyslexia, and specific language impairment (SLI) are relatively specific developmental learning disabilities in math, reading, and oral language, respectively, that occur in the context of average intellectual capacity and adequate environmental opportunities. Past research has been dominated by studies focused on single impairments despite the widespread recognition that overlapping and comorbid deficits are common. The present study took an epidemiological approach to study the learning profiles of a large school age sample in language, reading, and math. Both general learning profiles reflecting good or poor performance across measures and specific learning profiles involving either weak language, weak reading, weak math, or weak math and reading were observed. These latter four profiles characterized 70% of children with some evidence of a learning disability. Low scores in phonological short-term memory characterized clusters with a language-based weakness whereas low or variable phonological awareness was associated with the reading (but not language-based) weaknesses. The low math only group did not show these phonological deficits. These findings may suggest different etiologies for language-based deficits in language, reading, and math, reading-related impairments in reading and math, and isolated math disabilities. PMID:24155959

Peripheral facial weakness (Bell's palsy).

PubMed

Basić-Kes, Vanja; Dobrota, Vesna Dermanović; Cesarik, Marijan; Matovina, Lucija Zadro; Madzar, Zrinko; Zavoreo, Iris; Demarin, Vida

2013-06-01

Peripheral facial weakness is a facial nerve damage that results in muscle weakness on one side of the face. It may be idiopathic (Bell's palsy) or may have a detectable cause. Almost 80% of peripheral facial weakness cases are primary and the rest of them are secondary. The most frequent causes of secondary peripheral facial weakness are systemic viral infections, trauma, surgery, diabetes, local infections, tumor, immune disorders, drugs, degenerative diseases of the central nervous system, etc. The diagnosis relies upon the presence of typical signs and symptoms, blood chemistry tests, cerebrospinal fluid investigations, nerve conduction studies and neuroimaging methods (cerebral MRI, x-ray of the skull and mastoid). Treatment of secondary peripheral facial weakness is based on therapy for the underlying disorder, unlike the treatment of Bell's palsy that is controversial due to the lack of large, randomized, controlled, prospective studies. There are some indications that steroids or antiviral agents are beneficial but there are also studies that show no beneficial effect. Additional treatments include eye protection, physiotherapy, acupuncture, botulinum toxin, or surgery. Bell's palsy has a benign prognosis with complete recovery in about 80% of patients, 15% experience some mode of permanent nerve damage and severe consequences remain in 5% of patients.

Recommendations for postmarketing surveillance studies in haemophilia and other bleeding disorders.

PubMed

Lassila, R; Rothschild, C; De Moerloose, P; Richards, M; Perez, R; Gajek, H

2005-07-01

Prospective surveillance studies to monitor drug safety in the postapproval period are rarely employed systematically, although they are of greatest value for caregivers, drug users and regulatory authorities. Safety issues have affected not only conventional pharmaceuticals, but also especially coagulation factors in haemophilia treatment. The reputation of postmarketing surveillance (PMS) studies has been questionable, mainly due to their misuse to solicit prescriptions. Other weaknesses include inappropriate design, lack of standardized observation, limited follow-up periods, absence of rigour in identifying potential adverse drug effects, and infrequent publication. Although well-designed clinical trials represent the gold standard for generating sound clinical evidence, a number of aspects would make PMS studies valuable, if properly conducted. One of their main advantages is broader inclusion, and absence of an 'experimental' design. Lack of proper guidelines, and standardization may constitute a reason for the generally low quality of PMS studies. This paper proposes guidelines for haemophilia-specific PMS studies, in order to improve the acceptance of a basically valuable tool. In the absence of consistent regulatory guidance it will be especially important that the design and supervision of PMS studies involves physicians from the beginning. This will not only make such studies more scientifically relevant, but also help to implement them into daily clinical practice. Specifically in haemophilia, PMS studies may provide valuable data on clinical outcomes, or Quality of Life, which is of great importance when considering adequate standards of care in haemophilia patients.

Design of a 6-DOF upper limb rehabilitation exoskeleton with parallel actuated joints.

PubMed

Chen, Yanyan; Li, Ge; Zhu, Yanhe; Zhao, Jie; Cai, Hegao

2014-01-01

In this paper, a 6-DOF wearable upper limb exoskeleton with parallel actuated joints which perfectly mimics human motions is proposed. The upper limb exoskeleton assists the movement of physically weak people. Compared with the existing upper limb exoskeletons which are mostly designed using a serial structure with large movement space but small stiffness and poor wearable ability, a prototype for motion assistance based on human anatomy structure has been developed in our design. Moreover, the design adopts balls instead of bearings to save space, which simplifies the structure and reduces the cost of the mechanism. The proposed design also employs deceleration processes to ensure that the transmission ratio of each joint is coincident.

Pathogenesis of Fifth Metatarsal Fractures in College Soccer Players

PubMed Central

Fujitaka, Kohei; Taniguchi, Akira; Isomoto, Shinji; Kumai, Tsukasa; Otuki, Shingo; Okubo, Mamoru; Tanaka, Yasuhito

2015-01-01

Background: The pathogenesis of fifth metatarsal stress fractures remains uncertain. Hypothesis: Physical characteristics and environmental factors, which have received limited attention in the literature thus far, might be involved in the development of fifth metatarsal stress fractures. Study Design: Case-control study; Level of evidence, 3. Methods: To test the study hypothesis, a medical examination and survey of the living environment of collegiate soccer players was conducted and correlated with the existence of fifth metatarsal stress fractures. The survey and measurements were conducted in 273 male athletes from the same college soccer team between 2005 and 2013. A medical examination comprising assessment of stature, body weight, body mass index, foot–arch height ratio, toe-grip strength, quadriceps angle, leg-heel angle, functional reach test, single-leg standing time with eyes closed, straight-leg raise angle, finger-floor distance, heel-buttock distance, ankle joint range of motion, and a general joint laxity test were performed once a year, along with a questionnaire survey. The survey was also repeated when a fifth metatarsal stress fracture was diagnosed. The study participants were separated into a fifth metatarsal stress fracture injury group and a noninjury group. The measurement items and survey items were compared, and the association between the factors and the presence or absence of injuries was analyzed. Results: Toe-grip strength was significantly weaker in the injury group compared with the noninjury group, suggesting that weak toe-grip is associated with fifth metatarsal stress fracture (P < .05). In addition, fifth metatarsal stress fractures were more common in the nondominant leg (P < .05). Between-group comparisons of the other items showed no statistically significant differences. Conclusion: The association between weak toe-grip strength and fifth metatarsal fracture suggests that weak toe-grip may lead to an increase in the load applied onto the lateral side of the foot, resulting in stress fracture. The finding of stress fracture being more common in the nondominant leg needs further study. PMID:26535399

There may be Fermi Energy levels in the hollow interiors of Nanotubes that would allow for a type of Quantum

NASA Astrophysics Data System (ADS)

Kriske, Richard

2011-04-01

There may be Fermi Energy levels that would allow for easy travel by Atoms, Molecules and Particles, in the hollow interior of Nanotubes. This may result in a Quantum Mechanical explaination of Capillary Action, and it may result in devices could take advantage of the idea that it takes no energy to rise in a Capillary tube, only in leaving it. This no-energy conjecture of Capillarity sounds very much like the idea that Electrons in obitals lose no Energy staying in orbit, only in changing orbits.It is this conjecture that may reveal that a Fermi Energy state is essentially in a weak orbital. This weak orbital could be exploited to store Anti-matter for instance. More profoundly it clearly shows how the Quantum Mechanical states meld smoothly into Classical Physics. It also reveals how extremely efficient Classical Machines could be constructed to take advantage of this spontaneous action. Say a tube could be designed to nudge electrons out of a weak obital in one place, sent down the tube (which is another weak orbital) and deposited in a weak orbital of another very distant Atom, apparently with little or perhaps no work being done, as long as the orbitals are the same energy. This may already exist in some Biological systems. Although more experimentation is needed, this would be the breakthrough that is needed to unify Classical and Quantum Mechanics.

A systematic review of sensory-based treatments for children with disabilities.

PubMed

Barton, Erin E; Reichow, Brian; Schnitz, Alana; Smith, Isaac C; Sherlock, Daniel

2015-02-01

Sensory-based therapies are designed to address sensory processing difficulties by helping to organize and control the regulation of environmental sensory inputs. These treatments are increasingly popular, particularly with children with behavioral and developmental disabilities. However, empirical support for sensory-based treatments is limited. The purpose of this review was to conduct a comprehensive and methodologically sound evaluation of the efficacy of sensory-based treatments for children with disabilities. Methods for this review were registered with PROSPERO (CRD42012003243). Thirty studies involving 856 participants met our inclusion criteria and were included in this review. Considerable heterogeneity was noted across studies in implementation, measurement, and study rigor. The research on sensory-based treatments is limited due to insubstantial treatment outcomes, weak experimental designs, or high risk of bias. Although many people use and advocate for the use of sensory-based treatments and there is a substantial empirical literature on sensory-based treatments for children with disabilities, insufficient evidence exists to support their use. Copyright © 2014 Elsevier Ltd. All rights reserved.

A new front-face optical cell for measuring weak fluorescent emissions with time resolution in the picosecond time scale.

PubMed

Gryczynski, Z; Bucci, E

1993-11-01

Recent developments of ultrafast fluorimeters allow measuring time-resolved fluorescence on the picosecond time scale. This implies one is able to monitor lifetimes and anisotropy decays of highly quenched systems and of systems that contain fluorophores having lifetimes in the subnanosecond range; both systems that emit weak signals. The combination of weak signals and very short lifetimes makes the measurements prone to distortions which are negligible in standard fluorescence experiments. To cope with these difficulties, we have designed a new optical cell for front-face optics which offers to the excitation beam a horizontal free liquid surface in the absence of interactions with optical windows. The new cell has been tested with probes of known lifetimes and anisotropies. It proved very useful in detecting tryptophan fluorescence in hemoglobin. If only diluted samples are available, which cannot be used in front-face optics, regular square geometry can still be utilized by inserting light absorbers into a cuvette of 1 cm path length.

SWOT analysis in Sina Trauma and Surgery Research Center.

PubMed

Salamati, Payman; ashraf Eghbali, Ali; Zarghampour, Manijeh

2014-01-01

The present study was conducted with the aim of identifying and evaluating the internal and external factors, affecting the Sina Trauma and Surgery Research Center, affiliated to Tehran University of Medical Sciences and propose some of related strategies to senior managers. We used a combined quantitative and qualitative methodology. Our study population consisted of personnel (18 individuals) at Sina Trauma and Surgery Research Center. Data-collection tools were the group discussions and the questionnaires. Data were analyzed with descriptive statistics and SWOT (Strength, Weakness, Opportunities and Threats) analysis. 18 individuals participated in sessions, consisting of 8 women (44.4%) and 10 men (55.6%). The final scores were 2.45 for internal factors (strength-weakness) and 2.17 for external factors (opportunities-threats). In this study, we proposed 36 strategies (10 weakness-threat strategies, 10 weakness-opportunity strategies, 7 strength-threat strategies, and 9 strength-opportunity strategies). The current status of Sina Trauma and Surgery Research Center is threatened weak. We recommend the center to implement the proposed strategies.

Recovery of Weak Factor Loadings When Adding the Mean Structure in Confirmatory Factor Analysis: A Simulation Study

PubMed Central

Ximénez, Carmen

2016-01-01

This article extends previous research on the recovery of weak factor loadings in confirmatory factor analysis (CFA) by exploring the effects of adding the mean structure. This issue has not been examined in previous research. This study is based on the framework of Yung and Bentler (1999) and aims to examine the conditions that affect the recovery of weak factor loadings when the model includes the mean structure, compared to analyzing the covariance structure alone. A simulation study was conducted in which several constraints were defined for one-, two-, and three-factor models. Results show that adding the mean structure improves the recovery of weak factor loadings and reduces the asymptotic variances for the factor loadings, particularly for the models with a smaller number of factors and a small sample size. Therefore, under certain circumstances, modeling the means should be seriously considered for covariance models containing weak factor loadings. PMID:26779071

Parameter estimating state reconstruction

NASA Technical Reports Server (NTRS)

George, E. B.

1976-01-01

Parameter estimation is considered for systems whose entire state cannot be measured. Linear observers are designed to recover the unmeasured states to a sufficient accuracy to permit the estimation process. There are three distinct dynamics that must be accommodated in the system design: the dynamics of the plant, the dynamics of the observer, and the system updating of the parameter estimation. The latter two are designed to minimize interaction of the involved systems. These techniques are extended to weakly nonlinear systems. The application to a simulation of a space shuttle POGO system test is of particular interest. A nonlinear simulation of the system is developed, observers designed, and the parameters estimated.

Seat pressure measurement technologies: considerations for their evaluation.

PubMed

Gyi, D E; Porter, J M; Robertson, N K

1998-04-01

Interface pressure measurement has generated interest in the automotive industry as a technique which could be used in the prediction of driver discomfort for various car seat designs, and provide designers and manufacturers with rapid information early on in the design process. It is therefore essential that the data obtained are of the highest quality, relevant and have some quantitative meaning. Exploratory experimental work carried out with the commercially available Talley Pressure Monitor is outlined. This led to a better understanding of the strengths and weaknesses of this system and the re-design of the sensor matrix. Such evaluation, in the context of the actual experimental environment, is considered essential.

Constrained Aerothermodynamic Design of Hypersonic Vehicles

NASA Technical Reports Server (NTRS)

Gally, Tom; Campbell, Dick

2002-01-01

An investigation was conducted into possible methods of incorporating a hypersonic design capability with aerothermodynamic constraints into the CDISC aerodynamic design tool. The work was divided into two distinct phases: develop relations between surface curvature and hypersonic pressure coefficient which are compatible with CDISC's direct-iterative design method; and explore and implement possible methods of constraining the heat transfer rate over all or portions of the design surface. The main problem in implementing this method has been the weak relationship between surface shape and pressure coefficient at the stagnation point and the need to design around the surface blunt leading edge where there is a slope singularity. The final results show that some success has been achieved, but further improvements are needed.

Design of a 32-Channel EEG System for Brain Control Interface Applications

PubMed Central

Wang, Ching-Sung

2012-01-01

This study integrates the hardware circuit design and the development support of the software interface to achieve a 32-channel EEG system for BCI applications. Since the EEG signals of human bodies are generally very weak, in addition to preventing noise interference, it also requires avoiding the waveform distortion as well as waveform offset and so on; therefore, the design of a preamplifier with high common-mode rejection ratio and high signal-to-noise ratio is very important. Moreover, the friction between the electrode pads and the skin as well as the design of dual power supply will generate DC bias which affects the measurement signals. For this reason, this study specially designs an improved single-power AC-coupled circuit, which effectively reduces the DC bias and improves the error caused by the effects of part errors. At the same time, the digital way is applied to design the adjustable amplification and filter function, which can design for different EEG frequency bands. For the analog circuit, a frequency band will be taken out through the filtering circuit and then the digital filtering design will be used to adjust the extracted frequency band for the target frequency band, combining with MATLAB to design man-machine interface for displaying brain wave. Finally the measured signals are compared to the traditional 32-channel EEG signals. In addition to meeting the IFCN standards, the system design also conducted measurement verification in the standard EEG isolation room in order to demonstrate the accuracy and reliability of this system design. PMID:22778545

Design of a 32-channel EEG system for brain control interface applications.

PubMed

Wang, Ching-Sung

2012-01-01

This study integrates the hardware circuit design and the development support of the software interface to achieve a 32-channel EEG system for BCI applications. Since the EEG signals of human bodies are generally very weak, in addition to preventing noise interference, it also requires avoiding the waveform distortion as well as waveform offset and so on; therefore, the design of a preamplifier with high common-mode rejection ratio and high signal-to-noise ratio is very important. Moreover, the friction between the electrode pads and the skin as well as the design of dual power supply will generate DC bias which affects the measurement signals. For this reason, this study specially designs an improved single-power AC-coupled circuit, which effectively reduces the DC bias and improves the error caused by the effects of part errors. At the same time, the digital way is applied to design the adjustable amplification and filter function, which can design for different EEG frequency bands. For the analog circuit, a frequency band will be taken out through the filtering circuit and then the digital filtering design will be used to adjust the extracted frequency band for the target frequency band, combining with MATLAB to design man-machine interface for displaying brain wave. Finally the measured signals are compared to the traditional 32-channel EEG signals. In addition to meeting the IFCN standards, the system design also conducted measurement verification in the standard EEG isolation room in order to demonstrate the accuracy and reliability of this system design.

Multisite effectiveness trials of treatments for substance abuse and co-occurring problems: have we chosen the best designs?

PubMed

Nunes, Edward V; Ball, Samuel; Booth, Robert; Brigham, Gregory; Calsyn, Donald A; Carroll, Kathleen; Feaster, Daniel J; Hien, Denise; Hubbard, Robert L; Ling, Walter; Petry, Nancy M; Rotrosen, John; Selzer, Jeffrey; Stitzer, Maxine; Tross, Susan; Wakim, Paul; Winhusen, Theresa; Woody, George

2010-06-01

Multisite effectiveness trials such as those carried out in the National Drug Abuse Treatment Clinical Trials Network (CTN) are a critical step in the development and dissemination of evidence-based treatments because they address how such treatments perform in real-world clinical settings. As Brigham et al. summarized in a recent article (G. S. Brigham, D. J. Feaster, P. G. Wakim, & C. L. Dempsey C. L., 2009), several possible experimental designs may be chosen for such effectiveness trials. These include (a) a new treatment intervention (Tx) is compared to an existing mode of community based treatment as usual (TAU): Tx versus TAU; (b) a new intervention is added to TAU and compared to TAU alone: Tx + TAU versus TAU; or (c) a new intervention is added to TAU and compared to a control condition added to TAU: Tx + TAU versus control + TAU. Each of these designs addresses a different question and has different potential strengths and weaknesses. As of December 2009, the primary outcome paper had been published for 16 of the multisite randomized clinical trials conducted in the CTN, testing various treatments for drug abuse, HIV risk behavior, or related problems. This paper systematically examines, for each of the completed trials, the experimental design type chosen and its original rationale, the main findings of the trial, and the strengths and weaknesses of the design in hindsight. Based on this review, recommendations are generated to inform the design of future effectiveness trials on treatments for substance abuse, HIV risk, and other behavioral health problems.

Masked Visual Analysis: Minimizing Type I Error in Visually Guided Single-Case Design for Communication Disorders

PubMed Central

Hitchcock, Elaine R.; Ferron, John

2017-01-01

Purpose Single-case experimental designs are widely used to study interventions for communication disorders. Traditionally, single-case experiments follow a response-guided approach, where design decisions during the study are based on participants' observed patterns of behavior. However, this approach has been criticized for its high rate of Type I error. In masked visual analysis (MVA), response-guided decisions are made by a researcher who is blinded to participants' identities and treatment assignments. MVA also makes it possible to conduct a hypothesis test assessing the significance of treatment effects. Method This tutorial describes the principles of MVA, including both how experiments can be set up and how results can be used for hypothesis testing. We then report a case study showing how MVA was deployed in a multiple-baseline across-subjects study investigating treatment for residual errors affecting rhotics. Strengths and weaknesses of MVA are discussed. Conclusions Given their important role in the evidence base that informs clinical decision making, it is critical for single-case experimental studies to be conducted in a way that allows researchers to draw valid inferences. As a method that can increase the rigor of single-case studies while preserving the benefits of a response-guided approach, MVA warrants expanded attention from researchers in communication disorders. PMID:28595354

Masked Visual Analysis: Minimizing Type I Error in Visually Guided Single-Case Design for Communication Disorders.

PubMed

Byun, Tara McAllister; Hitchcock, Elaine R; Ferron, John

2017-06-10

Single-case experimental designs are widely used to study interventions for communication disorders. Traditionally, single-case experiments follow a response-guided approach, where design decisions during the study are based on participants' observed patterns of behavior. However, this approach has been criticized for its high rate of Type I error. In masked visual analysis (MVA), response-guided decisions are made by a researcher who is blinded to participants' identities and treatment assignments. MVA also makes it possible to conduct a hypothesis test assessing the significance of treatment effects. This tutorial describes the principles of MVA, including both how experiments can be set up and how results can be used for hypothesis testing. We then report a case study showing how MVA was deployed in a multiple-baseline across-subjects study investigating treatment for residual errors affecting rhotics. Strengths and weaknesses of MVA are discussed. Given their important role in the evidence base that informs clinical decision making, it is critical for single-case experimental studies to be conducted in a way that allows researchers to draw valid inferences. As a method that can increase the rigor of single-case studies while preserving the benefits of a response-guided approach, MVA warrants expanded attention from researchers in communication disorders.

Prevalence of clinically relevant muscle weakness and its association with vitamin D status among older adults in Ecuador.

PubMed

Orces, Carlos H

2017-10-01

Muscle weakness and 25-hydroxyvitamin D (25(OH)D) deficiency have been associated with adverse outcomes among older adults. However, little is known about the relationship between clinically relevant muscle weakness and 25(OH)D levels in Ecuador. To examine the prevalence of muscle weakness and its association with 25(OH)D status among subjects aged 60 years and older in Ecuador. The present study was based on data from 2205 participants in the first National Survey of Health, Wellbeing, and Aging. The Foundation for the National Institute of Health Sarcopenia Project criteria was used to examine muscle weakness prevalence rates. Gender-specific general linear and logistic regression models adjusted for potential confounders were created to compare mean 25(OH)D concentrations and 25(OH)D deficiency across muscle strength categories, respectively. An estimated 32.2% of women and 33.4% of men had evidence of clinically relevant muscle weakness in Ecuador. In general, increased muscle weakness prevalence rates were present among Indigenous, residents in the rural Andes Mountains, underweight subjects, and those with a sedentary lifestyle. Muscle strength was significantly and directly correlated with mean 25(OH)D levels. After controlling for potential confounders, 25(OH)D deficiency prevalence rates were 31 and 43% higher among men and women with muscle weakness than those with normal strength, respectively. One-third of older adults nationwide had evidence of muscle weakness. While the present study found a significant correlation between muscle strength and 25(OH)D concentrations, further research is needed to examine whether optimizing 25(OH)D levels may improve muscle weakness among older adults.

Preceding weak noise sharpens the frequency tuning and elevates the response threshold of the mouse inferior collicular neurons through GABAergic inhibition.

PubMed

Wang, Xin; Jen, Philip H-S; Wu, Fei-Jian; Chen, Qi-Cai

2007-09-05

In acoustic communication, animals must extract biologically relevant signals that are embedded in noisy environment. The present study examines how weak noise may affect the auditory sensitivity of neurons in the central nucleus of the mouse inferior colliculus (IC) which receives convergent excitatory and inhibitory inputs from both lower and higher auditory centers. Specifically, we studied the frequency sensitivity and minimum threshold of IC neurons using a pure tone probe and a weak white noise masker under forward masking paradigm. For most IC neurons, probe-elicited response was decreased by a weak white noise that was presented at a specific gap (i.e. time window). When presented within this time window, weak noise masking sharpened the frequency tuning curve and increased the minimum threshold of IC neurons. The degree of weak noise masking of these two measurements increased with noise duration. Sharpening of the frequency tuning curve and increasing of the minimum threshold of IC neurons during weak noise masking were mostly mediated through GABAergic inhibition. In addition, sharpening of frequency tuning curve by the weak noise masker was more effective at the high than at low frequency limb. These data indicate that in the real world the ambient noise may improve frequency sensitivity of IC neurons through GABAergic inhibition while inevitably decrease the frequency response range and sensitivity of IC neurons.

Asymmetric Weakness and West Nile Virus Infection.

PubMed

Kuo, Dick C; Bilal, Saadiyah; Koller, Paul

2015-09-01

Weakness is a common presentation in the emergency department (ED). Asymmetric weakness or weakness that appears not to follow an anatomical pattern is a less common occurrence. Acute flaccid paralysis with no signs of meningoencephalitis is one of the more uncommon presentations of West Nile virus (WNV). Patient may complain of an acute onset of severe weakness, or even paralysis, in one or multiple limbs with no sensory deficits. This weakness is caused by injury to the anterior horn cells of the spinal cord. We present a case of acute asymmetric flaccid paralysis with preserved sensory responses that was eventually diagnosed as neuroinvasive WNV infection. A 31-year-old male with no medical history presented with complaints of left lower and right upper extremity weakness. Computed tomography scan was negative and multiple other studies were performed in the ED. Eventually, he was admitted to the hospital and was found to have decreased motor amplitudes, severely reduced motor neuron recruitment, and denervation on electrodiagnostic study. Cerebrospinal fluid specimen tested positive for WNV immunoglobulin (Ig) G and IgM antibodies. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Acute asymmetric flaccid paralysis with no signs of viremia or meningoencephalitis is an unusual presentation of WNV infection. WNV should be included in the differential for patients with asymmetric weakness, especially in the summer months in areas with large mosquito populations. Copyright © 2015 Elsevier Inc. All rights reserved.

Evaluating arguments during instigations of defence motivation and accuracy motivation.

PubMed

Liu, Cheng-Hong

2017-05-01

When people evaluate the strength of an argument, their motivations are likely to influence the evaluation. However, few studies have specifically investigated the influences of motivational factors on argument evaluation. This study examined the effects of defence and accuracy motivations on argument evaluation. According to the compatibility between the advocated positions of arguments and participants' prior beliefs and the objective strength of arguments, participants evaluated four types of arguments: compatible-strong, compatible-weak, incompatible-strong, and incompatible-weak arguments. Experiment 1 revealed that participants possessing a high defence motivation rated compatible-weak arguments as stronger and incompatible-strong ones as weaker than participants possessing a low defence motivation. However, the strength ratings between the high and low defence groups regarding both compatible-strong and incompatible-weak arguments were similar. Experiment 2 revealed that when participants possessed a high accuracy motivation, they rated compatible-weak arguments as weaker and incompatible-strong ones as stronger than when they possessed a low accuracy motivation. However, participants' ratings on both compatible-strong and incompatible-weak arguments were similar when comparing high and low accuracy conditions. The results suggest that defence and accuracy motivations are two major motives influencing argument evaluation. However, they primarily influence the evaluation results for compatible-weak and incompatible-strong arguments, but not for compatible-strong and incompatible-weak arguments. © 2016 The British Psychological Society.

Improving Familytalk: Educating Families to Work Better.

ERIC Educational Resources Information Center

Barret, Robert L.

1982-01-01

Describes a structured group designed for families that include adolescents. The workshop, "Improving Familytalk": (1) assesses communication skills and weaknesses in families, (2) teaches improved communication skills, (3) applies skills by talking about problems and expectations, and (4) teaches how to build positive aspects of family life. (JAC)

The Gulf War on Computer: A Review of "Iraq Stack."

ERIC Educational Resources Information Center

Rattan, Dick

1993-01-01

Reviews a HyperCard stack designed for use in schools and at home. Describes the program as primarily a database of information on Iraq, Kuwait, and the Gulf War. Contends that the program is pedagogically weak and of marginal use in the classroom. (CFR)

Geotextile reinforcement of low-bearing capacity soils: comparison of two design methods applicable to thawing soils

DOT National Transportation Integrated Search

1999-06-01

Thawing fine-grained soils are often saturated and have extremely low bearing capacity. Geosynthetics are used to reinforce unsurfaced roads on weak, saturated soils and therefore are good candidates for use in stabilization of thawing soils. To stab...

Elementary Mathematics: Not so Elementary

ERIC Educational Resources Information Center

Scillieri, Elissa Mains

2012-01-01

International tests indicate that United States students have been outscored by other countries in the area of mathematics. Researchers warn that elementary mathematics curricula and instruction in this country is not designed around helping students achieve mathematics proficiency. Much of this could also be attributed to the weak development and…

Beyond the Buzzwords: Delivering Diversity Training that Makes a Difference.

ERIC Educational Resources Information Center

Cornell, Sylvia Ryce

This document contains materials for a 3-hour diversity awareness workshop designed to help trainers accomplish the following: identify their strengths, weaknesses, and impact on others; develop an increased awareness of cultural stereotypes; master techniques for defusing hostility, handling difficult students and coworkers, and turning…

Study designs for determining and comparing sensitivities of disease screening tests.

PubMed

Prorok, Philip C; Kramer, Barnett S; Miller, Anthony B

2015-12-01

To investigate the capability of various study designs to determine the sensitivity of a disease screening test. Quantities that can be calculated from these designs were derived and examined for their relationship to true sensitivity (the ability to detect unrecognized disease that would surface clinically in the absence of screening) and overdiagnosis. To examine the sensitivity of one test, the single cohort design, in which all participants receive the test, is particularly weak, providing only an upper bound on the true sensitivity, and yields no information about overdiagnosis. A randomized design, with one control arm and participants tested in the other, that includes sufficient post-screening follow-up, allows calculation of bounds on, and an approximation to, true sensitivity and also determination of overdiagnosis. Without follow-up, bounds on the true sensitivity can be calculated. To compare two tests, the single cohort paired design in which all participants receive both tests is precarious. The three arm randomized design with post screening follow-up is preferred, yielding an approximation to the true sensitivity, bounds on the true sensitivity, and the extent of overdiagnosis of each test. Without post screening follow-up, bounds on the true sensitivities can be calculated. When an unscreened control arm is not possible, the two-arm randomized design is recommended. Individual test sensitivities cannot be determined, but with sufficient post-screening follow-up, an order relationship can be established, as can the difference in overdiagnosis between the two tests. © The Author(s) 2015.

Application of self-balanced loading test to socketed pile in weak rock

NASA Astrophysics Data System (ADS)

Cheng, Ye; Gong, Weiming; Dai, Guoliang; Wu, JingKun

2008-11-01

Method of self-balanced loading test differs from the traditional methods of pile test. The key equipment of the test is a cell. The cell specially designed is used to exert load which is placed in pile body. During the test, displacement values of the top plate and the bottom plate of the cell are recorded according to every level of load. So Q-S curves can be obtained. In terms of test results, the bearing capacity of pile can be judged. Equipments of the test are simply and cost of it is low. Under some special conditions, the method will take a great advantage. In Guangxi Province, tertiary mudstone distributes widely which is typical weak rock. It is usually chosen as the bearing stratum of pile foundation. In order to make full use of its high bearing capacity, pile is generally designed as belled pile. Foundations of two high-rise buildings which are close to each other are made up of belled socketed piles in weak rock. To obtain the bearing capacity of the belled socketed pile in weak rock, loading test in situ should be taken since it is not reasonable that experimental compression strength of the mudstone is used for design. The self-balanced loading test was applied to eight piles of two buildings. To get the best test effect, the assembly of cell should be taken different modes in terms of the depth that pile socketed in rock and the dimension of the enlarged toe. The assembly of cells had been taken three modes, and tests were carried on successfully. By the self-balanced loading test, the large bearing capacities of belled socketed piles were obtained. Several key parameters required in design were achieved from the tests. For the data of tests had been analyzed, the bearing performance of pile tip, pile side and whole pile was revealed. It is further realized that the bearing capacity of belled socketed pile in the mudstone will decrease after the mudstone it socketed in has been immerged. Among kinds of mineral ingredient in the mudstone, montmorillonite is much. And in the size composition, content of cosmid is high. For specific surface area of cosmid is large and water intake capacity of it is strong, water content has great effect on strength of the mudstone. Along with water content increasing, strength of the mudstone declines nonlinear apparently. Since effective measures had been taken, the mudstone was prohibited from being immerged during construction. And valuable experience has been accumulated for similar projects construction henceforth.

The Intelligent Control System and Experiments for an Unmanned Wave Glider.

PubMed

Liao, Yulei; Wang, Leifeng; Li, Yiming; Li, Ye; Jiang, Quanquan

2016-01-01

The control system designing of Unmanned Wave Glider (UWG) is challenging since the control system is weak maneuvering, large time-lag and large disturbance, which is difficult to establish accurate mathematical model. Meanwhile, to complete marine environment monitoring in long time scale and large spatial scale autonomously, UWG asks high requirements of intelligence and reliability. This paper focuses on the "Ocean Rambler" UWG. First, the intelligent control system architecture is designed based on the cerebrum basic function combination zone theory and hierarchic control method. The hardware and software designing of the embedded motion control system are mainly discussed. A motion control system based on rational behavior model of four layers is proposed. Then, combining with the line-of sight method(LOS), a self-adapting PID guidance law is proposed to compensate the steady state error in path following of UWG caused by marine environment disturbance especially current. Based on S-surface control method, an improved S-surface heading controller is proposed to solve the heading control problem of the weak maneuvering carrier under large disturbance. Finally, the simulation experiments were carried out and the UWG completed autonomous path following and marine environment monitoring in sea trials. The simulation experiments and sea trial results prove that the proposed intelligent control system, guidance law, controller have favorable control performance, and the feasibility and reliability of the designed intelligent control system of UWG are verified.

The Intelligent Control System and Experiments for an Unmanned Wave Glider

PubMed Central

Liao, Yulei; Wang, Leifeng; Li, Yiming; Li, Ye; Jiang, Quanquan

2016-01-01

The control system designing of Unmanned Wave Glider (UWG) is challenging since the control system is weak maneuvering, large time-lag and large disturbance, which is difficult to establish accurate mathematical model. Meanwhile, to complete marine environment monitoring in long time scale and large spatial scale autonomously, UWG asks high requirements of intelligence and reliability. This paper focuses on the “Ocean Rambler” UWG. First, the intelligent control system architecture is designed based on the cerebrum basic function combination zone theory and hierarchic control method. The hardware and software designing of the embedded motion control system are mainly discussed. A motion control system based on rational behavior model of four layers is proposed. Then, combining with the line-of sight method(LOS), a self-adapting PID guidance law is proposed to compensate the steady state error in path following of UWG caused by marine environment disturbance especially current. Based on S-surface control method, an improved S-surface heading controller is proposed to solve the heading control problem of the weak maneuvering carrier under large disturbance. Finally, the simulation experiments were carried out and the UWG completed autonomous path following and marine environment monitoring in sea trials. The simulation experiments and sea trial results prove that the proposed intelligent control system, guidance law, controller have favorable control performance, and the feasibility and reliability of the designed intelligent control system of UWG are verified. PMID:28005956

Rotor design of high tip speed low loading transonic fan.

NASA Technical Reports Server (NTRS)

Erwin, J. R.; Vitale, N. G.

1972-01-01

This paper describes the design concepts, principles and details of a high tip speed transonic rotor having low aerodynamic loading. The purpose of the NASA sponsored investigation was to determine whether good efficiency and large stall margin could be obtained by designing a rotor to avoid flow separation associated with strong normal shocks. Fully supersonic flow through the outboard region of the rotor with compression accomplished by weak oblique shocks were major design concepts employed. Computer programs were written and used to derive blade sections consistent from the all-supersonic tip region to the all-subsonic hub region. Preliminary test results indicate attainment of design pressure ratio and design flow at design speed with about a 1.6 point decrement in efficiency and large stall margin.

Evaluating disease management programme effectiveness: an introduction to the regression discontinuity design.

PubMed

Linden, Ariel; Adams, John L; Roberts, Nancy

2006-04-01

Although disease management (DM) has been in existence for over a decade, there is still much uncertainty as to its effectiveness in improving health status and reducing medical cost. The main reason is that most programme evaluations typically follow weak observational study designs that are subject to bias, most notably selection bias and regression to the mean. The regression discontinuity (RD) design may be the best alternative to randomized studies for evaluating DM programme effectiveness. The most crucial element of the RD design is its use of a 'cut-off' score on a pre-test measure to determine assignment to intervention or control. A valuable feature of this technique is that the pre-test measure does not have to be the same as the outcome measure, thus maximizing the programme's ability to use research-based practice guidelines, survey instruments and other tools to identify those individuals in greatest need of the programme intervention. Similarly, the cut-off score can be based on clinical understanding of the disease process, empirically derived, or resource-based. In the RD design, programme effectiveness is determined by a change in the pre-post relationship at the cut-off point. While the RD design is uniquely suitable for DM programme evaluation, its success will depend, in large part, on fundamental changes being made in the way DM programmes identify and assign individuals to the programme intervention.

Extrapolating surface structures to depth in transpressional systems: the role of rheology and convergence angle deduced from analogue experiments

NASA Astrophysics Data System (ADS)

Hsieh, S. Y.; Neubauer, F.; Willingshofer, E.; Sokoutis, D.

2014-12-01

The internal structure of major strike-slip faults is still poorly understood, particularly how the deep structure could be inferred from its surface expression (Molnar and Dayem, 2011). Previous analogue experiments suggest that the convergence angle is the most influential factor (Leever et al., 2011). Further analogue modeling may allow a better understanding how to extrapolate surface structures to the subsurface geometry of strike-slip faults. Various scenarios of analogue experiments were designed to represent strike-slip faults in nature from different geological settings. As such key parameters, which are investigated in this study include: (a) the angle of convergence, (b) the thickness of brittle layer, (c) the influence of a rheological weak layer within the crust, and (d) influence of a thick and rheologically weak layer at the base of the crust. The latter aimed to simulate the effect of a hot metamorphic core complex or an alignment of uprising plutons bordered by a transtensional/transpressional strike-slip fault. The preliminary results show that convergence angle significantly influences the overall geometry of the transpressive system with greater convergence angles resulting in wider fault zones and higher elevation. Different positions, densities and viscosities of weak rheological layers have not only different surface expressions but also affect the fault geometry in the subsurface. For instance, rheological weak material in the bottom layer results in stretching when experiment reaches a certain displacement and a buildup of a less segmented, wide positive flower structure. At the surface, a wide fault valley in the middle of the fault zone is the reflection of stretching along the velocity discontinuity at depth. In models with a thin and rheologically weaker layer in the middle of the brittle layer, deformation is distributed over more faults and the geometry of the fault zone below and above the weak zone shows significant differences. This latter experiment has significantly similar phenomena in reality, such as few pressure ridges along Altyn fault. The experimental results underline the need to understand the role of the convergence angle and the influence of rheology on fault evolution, in order to connect between surface deformation and subsurface geometry.

Narrative comprehension in 4-7-year-old children with autism: testing the Weak Central Coherence account.

PubMed

Nuske, Heather Joy; Bavin, Edith L

2011-01-01

Despite somewhat spared structural language development in high-functioning autism, communicative comprehension deficits persist. Comprehension involves the integration of meaning: global processing is required. The Weak Central Coherence theory suggests that individuals with autism are biased to process information locally. This cognitive style may impair comprehension, particularly if inferencing is required. However, task performance may be facilitated by this cognitive style if local processing is required. The current study was designed to examine the extent to which the 'weak central coherence' cognitive style affects comprehension and inferential processing of spoken narratives. The children with autism were expected to perform comparatively poorer on inferences relating to event scripts and comparatively better on inferences requiring deductive reasoning. Fourteen high-functioning children with autism were recruited from databases of various autism organizations (mean age = 6:7, 13 males, one female) and were matched on a receptive vocabulary and a picture-completion task with 14 typically developing children recruited from a local childcare centre (mean age = 4:10, seven males, seven females). The children were read short stories and asked questions about the stories. Results indicated that the children with autism were less able to make inferences based on event scripts, but the groups did not differ significantly on inferences requiring deductive logical reasoning. Despite similar group performance on questions relating to the main idea of the stories, only for the typically developing group was good performance on extracting the main idea of the narratives significantly correlated with performance on all other comprehension tasks. Findings provide some support for the Weak Central Coherence theory and demonstrate that young children with autism do not spontaneously integrate information in order to make script inferences, as do typically developing children. These findings may help to explain communicative problems of young children with autism and can be applied to intervention programme development. More research on the link between a 'weak central coherence' cognitive style and communicative comprehension in autism will be valuable in understanding the comprehension deficits associated with autism. © 2010 Royal College of Speech & Language Therapists.

Preliminary results on an H-alpha map of the Gum nebula obtained with the D-z-A satellite

NASA Technical Reports Server (NTRS)

Blamont, J. E.; Levasseur, A. C.

1971-01-01

Hydrogen emissions, including telluric H alpha, in the terrestrial atmosphere were studied. The H alpha experiment was designed to use a monochromatic photometer that would provide measurements of weak H alpha emission originating at altitudes of a few hundred or thousand km, free of contamination by other telluric emissions. The Gum nebula was recorded by the instrument as a much more intense feature than the geocoronal emission. The spacecraft employed and the optical onboard equipment are described. Field of view, spectral response, absolute calibration, linearity, and inflight performance are discussed.

Implementation and Evaluation of Multiple Adaptive Control Technologies for a Generic Transport Aircraft Simulation

NASA Technical Reports Server (NTRS)

Campbell, Stefan F.; Kaneshige, John T.; Nguyen, Nhan T.; Krishakumar, Kalmanje S.

2010-01-01

Presented here is the evaluation of multiple adaptive control technologies for a generic transport aircraft simulation. For this study, seven model reference adaptive control (MRAC) based technologies were considered. Each technology was integrated into an identical dynamic-inversion control architecture and tuned using a methodology based on metrics and specific design requirements. Simulation tests were then performed to evaluate each technology s sensitivity to time-delay, flight condition, model uncertainty, and artificially induced cross-coupling. The resulting robustness and performance characteristics were used to identify potential strengths, weaknesses, and integration challenges of the individual adaptive control technologies

Therapeutic touch: is there a scientific basis for the practice?

PubMed

Clark, P E; Clark, M J

1984-01-01

The research-related literature on the topic of therapeutic touch is critically reviewed. The purpose of the review is to explore the current scientific basis for the teaching and practice of therapeutic touch as a treatment modality. An examination of published research literature indicates that empirical support for the practice of therapeutic touch is, at best, weak. The results of well-designed, double-blind studies have been transient, of no significance, or are in need of independent replication. Current practice of therapeutic touch is empirically little more than practice of placebo. Considerations for further nursing research are also presented.

A psycho-historical research program for the integrative science of art.

PubMed

Bullot, Nicolas J; Reber, Rolf

2013-04-01

Critics of the target article objected to our account of art appreciators' sensitivity to art-historical contexts and functions, the relations among the modes of artistic appreciation, and the weaknesses of aesthetic science. To rebut these objections and justify our program, we argue that the current neglect of sensitivity to art-historical contexts persists as a result of a pervasive aesthetic–artistic confound; we further specify our claim that basic exposure and the design stance are necessary conditions of artistic understanding; and we explain why many experimental studies do not belong to a psycho-historical science of art.

The Power of Theory, Research Design, and Transdisciplinary Integration in Moving Psychopathology Forward.

PubMed

Vaidyanathan, Uma; Vrieze, Scott I; Iacono, William G

While the past few decades have seen much work in psychopathology research that has yielded provocative insights, relatively little progress has been made in understanding the etiology of mental disorders. We contend that this is due to an overreliance on statistics and technology with insufficient attention to adequacy of experimental design, a lack of integration of data across various domains of research, and testing of theoretical models using relatively weak study designs. We provide a conceptual discussion of these issues and follow with a concrete demonstration of our proposed solution. Using two different disorders - depression and substance use - as examples, we illustrate how we can evaluate competing theories regarding their etiology by integrating information from various domains including latent variable models, neurobiology, and quasi-experimental data such as twin and adoption studies, rather than relying on any single methodology alone. More broadly, we discuss the extent to which such integrative thinking allows for inferences about the etiology of mental disorders, rather than focusing on descriptive correlates alone. Greater scientific insight will require stringent tests of competing theories and a deeper conceptual understanding of the advantages and pitfalls of methodologies and criteria we use in our studies.

Tailored Prevention of Inpatient Falls

PubMed Central

ZUYEV, LYUBOV; BENOIT, ANGELA N.; CHANG, FRANK Y.; DYKES, PATRICIA C.

2011-01-01

Patient falls and fall-related injuries are serious problems in hospitals. The Fall TIPS application aims to prevent patient falls by translating routine nursing fall risk assessment into a decision support intervention that communicates fall risk status and creates a tailored evidence-based plan of care that is accessible to the care team, patients, and family members. In our design and implementation of the Fall TIPS toolkit, we used the Spiral Software Development Life Cycle model. Three output tools available to be generated from the toolkit are bed poster, plan of care, and patient education handout. A preliminary design of the application was based on initial requirements defined by project leaders and informed by focus groups with end users. Preliminary design partially simulated the paper version of the Morse Fall Scale currently used in hospitals involved in the research study. Strengths and weaknesses of the first prototype were identified by heuristic evaluation. Usability testing was performed at sites where research study is implemented. Suggestions mentioned by end users participating in usability studies were either directly incorporated into the toolkit and output tools, were slightly modified, or will be addressed during training. The next step is implementation of the fall prevention toolkit on the pilot testing units. PMID:20975543

Super-quantum correlation for SU(2) invariant state in 4⊗ 2 system

NASA Astrophysics Data System (ADS)

Li, Lin-Song; Tao, Yuan-Hong; Nan, Hua; Xu, Hui

2018-04-01

We analytically evaluate the weak one-way deficit and super-quantum discord for a system composed of spin-3/2 and spin-1/2 subsystems possessing SU(2) symmetry. We also make a comparative study of the relationships among the quantum discord, one-way deficit, weak one-way deficit, and super-quantum discord for the SU(2) invariant state. It is shown that super-quantum discord via weak measurement is greater than that via von Neumann measurement. But weak one-way deficit is less than the one-way deficit. As a result, weak measurement do not always reveal more quantumness.

Space station definitions, design, and development. Task 5: Multiple arm telerobot coordination and control: Manipulator design methodology

NASA Technical Reports Server (NTRS)

Stoughton, R. M.

1990-01-01

A proposed methodology applicable to the design of manipulator systems is described. The current design process is especially weak in the preliminary design phase, since there is no accepted measure to be used in trading off different options available for the various subsystems. The design process described uses Cartesian End-Effector Impedance as a measure of performance for the system. Having this measure of performance, it is shown how it may be used to determine the trade-offs necessary to the preliminary design phase. The design process involves three main parts: (1) determination of desired system performance in terms of End-Effector Impedance; (2) trade-off design options to achieve this desired performance; and (3) verification of system performance through laboratory testing. The design process is developed using numerous examples and experiments to demonstrate the feasability of this approach to manipulator design.